After a long (time rest/break)，I was going to find a job, but the employment situation washad become worse and worse, especially because of the dropping ofecline in the economy after epithe pandemic.

Recently, I just geot a offer aboutof a job in marketing, t. The main task is to sell car's insurance.

"car insurance" is a well known concept

Actually, I had fewlittle experience in this area, and felt shy to communicateing with strangers, however the job just needed the worker to contact people passionately.But I was urgently trying to find a job, so I just encouragetold myself that I can do it！ But fineventually I quited it the job because of the poor benefits and excessive requirements.

"quit" is its own past tense, most words in English don't work like that, but quit is one that does

It was hard to find a good job, but through (endeavoursring / trying) constantly, I got another opportunity to interview.

endeavoring is the grammatically correct version of your initial version, but most English speakers would just use trying here.

This position was aboutfor a auxiliary teacher, to help the teacher prepare teaching materials and urgent students to study hard.

"urgent" = needed very quickly
"urge" = to encourage strongly

It seemed easy, but required some Chinese or English ability not basicallyat a higher than basic level.

But I was not good at neither of them.

"not" ... "at neither" is a double negative, which you should avoid.

After twenty-five years of struggling, I just quited dreaming of native talent, so I instantly transferswitched to learning English to assist me pass this interview.

Not quite sure what you mean by "native talent" here

By the way, the reason why I was so self-confident to itfor the interview is that there are only basic English requirements.

FORor finding a job

After a long time rest，I was going to find a job, but the employment situation was becoame worse and worse, especially because ofdue to the dropp ing of economy after the epidemic.

There is only one epidemic that we are referring to here, so we put the before it.

Recently, I just get an offer about marketing, the main task is to sell car's insurance.

The word "a" before a vowel sound becomes "an". For example:
A book
An instrument
An hour (h is not a vowel, but the first sound in hour is a vowel sound, so a becomes an.)

Actually, I had a few experiences in this area, and felt shy to communicate with strangers, h. However the job just needs the worker to contact people passionately.But I was I urgently needed to find a job, so I just encouraged myself that I can do it！ But finallyI'm the end I quited it because of the poor benefits and excessive requirements.

It was hard to find a good job, but through endeavours constantlyconstant searching, I got another opportunity to interview.

Endeavors is a good word but it doesn't fit this context well. Endeavors usually implies something epic, for example his endeavors during the wartime.

This position was abouts an auxiliary teacher, to help teachers prepare teaching materials and to urgent students to study hard.

It seemed easy, but required some Chinese or English ability not basically.

Not sure what you meant by not basically at the end

But I was not good at neither of them.

Not good at neither is a double negative and sounds strange. You can say this in two ways:
I was not good at either of them
I was good at neither of them

After twenty-five years of struggling, I just quited dreaming of nativeural talent, so I instantly transfered to learn English to assisthelp me pass this interview.

By the way, whythe reason that I was so self-confident to it is that there are only basic English requirements.

FORor finding a job

Very nitpicky, but you don’t really need “for” to be in caps lock (FOR), unless I’m just fully missing a reason or meaning behind it (which I very well could be)

After a long time rest，, I was going to find a job, but the employment situation was becomeing worse and worse, especially because of the droppeclinge of the economy after the epidemic.

“Time” isn’t necessary here, as “long” already implies that you are talking about a long or extended period of time (mainly due to “rest” not really being a noun that can be described with physical length I think)

While “after a long rest” is ok in the sense that it gets the meaning across with the context of the whole sentence, I think “After being unemployed for a long time” might be clearer and more natural.

The article “the” is needed before “employment situation”, “economy” and “epidemic” here.

“Become” —> “becoming”
This is because you are writing in the past tense here (indicated by the numerous uses of “was”, and hence “become” would change to “becoming”. This is also because “become” is mainly used in the present tense.

“Decline” is a lot more natural compared to “dropping”.

Recently, I just gegot an offer about marketing, where the main task is to sell car's insurance.

The first comma is unnecessary, but it’s not completely wrong to have it there.

I removed “just” because it implies the same thing as “recently” (so you would have one or the other - “recently I got an offer about marketing” or “I just got an offer about marketing”). There’s only a slight nuance/difference between the two, which is that “just” makes it feel a lot more recent, as if it happened only a few minutes or even just a second before beginning to write this. “Recently” feels more as if this event could’ve happened at any time in the past few days.

“Get” —> “got”
“Get” is only really used in the present tense (same as with “become” earlier), whereas “got” is used in the past tense.

“A” —> “an”
“Offer” begins with a vowel, so you would use “an”.

I added “where” to better connect the two clauses. Alternatively, you also could have just started a new sentence with “The main task is to sell car insurance”.

“Car’s insurance” —> “car insurance”
The “ ‘s “ would essentially imply that the insurance belongs to the car. While that is kind of true in the sense that the insurance does heavily relate to the car, the proper phrase would be “car insurance”

Actually, I had fewsome experience in this area, andbut I felt too shy to communicate with strangers, however even though the job just needed the worker to contact people passionateinteract with people enthusiastically. But I was urgentlydesperate to find a job, so I just encouragconvinced myself that I canould do it！! But I finally I quited it because of the poor benefiresults and excessive requirements.

(These first few corrections might not actually be fully accurate to what you wanted to say, but I’m keeping them here in case you find them useful)
“Few” —> “some”
“Few” would more typically be used in the phrase “a few”, which would be used if you had said “experiences” (So it would become “a few experiences”). However, “some experience” is the more accurate and natural expression here.

I changed “and” and “however” because I found it confusing with those word choices. I’m not really sure if my choices are what you meant because it still feels a little confusing.

Adding “too” emphasises the point about you being shy, which made it hard or even, in a way, impossible to communicate with strangers.

“Need” —> “needed”
(So it’s in past tense)

“Interact with people enthusiastically” sounds more natural to me.

(This is the end of the possibly not entirely accurate corrections. Essentially I copied your native text into Google Translate to try to get an idea of what you wanted to say, even though Google Translate isn’t always entirely accurate. I believe what is potentially more accurate to what you wanted to say using the translation provided would be “Actually, I had no experience in this area and felt that I would be too shy to communicate with strangers, however the job needed/required the worker to interact with people enthusiastically”.)

You could say “I was desperate to find a job” or “I urgently needed to find a job”

For “encouraged” to make sense here you’d have to make a lot of changes, so changing it to “convinced” would probably be the simplest solution.

“Could” feels more consistent with the tense. I believe there’s a proper word and explanation for the tense, but I’m not really sure what it’s called. It might be related to the ‘conditional’ (mood?) based off my limited experience with its equivalent in French, so if you’re interested you could check

I prefer the word order with “finally” being after “I”.

“Quit” is one of those weird verbs that can stay the same in both the present and past tense. However, there’s a chance that “quitted” with a double T is technically correct, although it is not commonly used at all.

“It” is unnecessary here because the context of the sentence makes it clear that you’re talking about the job.

“Because” —> “because of”
Just “because” would be used more so to connect 2 independent clauses (so things that could be their own sentence). For example “I finally quit because there were so many poor results and excessive requirements”.
“The poor results and excessive requirements” isn’t its own sentence, so you would add “of” so it becomes “because of”.

I changed “benefits” because the word itself implies that whatever it refers to absolutely has to be positive, which is contradicted by the use of the adjective “poor”. I’m not so sure that “results” is necessarily the best choice, but it’s the only neutral word that I could think of.

It was hard to find a good job, but through constant endeavours constantly, I got another opportunity tofor an interview.

“Constant endeavours” would be the proper phrase.

“To interview” makes it sound more as if you’re going to be the one interviewing someone else. Continuing to use “interview” as a verb would make it a lot longer, so I changed it to “for an interview” to make it a noun, and to also simplify the sentence a little.

This position was aboutfor/to be an auxiliary teacher, to helpwhich helps the teacher to prepare teaching materials and urgents students to study hard.

“This position was for an auxiliary teacher” or “this position was to be an auxiliary teacher” would make more sense.

“Which” would connect it all a little better. Because of this change, I also had to change “help” to “helps” (and also the part with “urges”, which I will explain more later).

You would need to “the” before “teacher”.

The “to” in “to prepare teaching materials” isn’t necessary, it’s just a personal preference of mine.

“Urgent” is an adjective. “Urge” or “urges” would be the verb (but a random note: while writing this my keyboard did autocorrect “urge” to “urgent”)

It seemed easy, but required some Chinese or English ability notskills beyond the basically ones.

I’m not so sure about my wording with the last part - it’s technically correct but it also still feels a little confusing.

But I was not good at neither of them.

You wouldn’t have “not” and “neither” in the same sentence because they kind of contradict each other.
It would either be “But I was not good at either of them” or “but I was good at neither of them”.
Personally I’d choose the first option, which is what I’ve corrected it to.

After twenty-five years of struggling, I just quited dreaming of nativeural talent, so I instantly transferdecided to learn English to assist me in passing this interview.

“Quit dreaming of natural talent” feels so harsh and I feel really mean correcting it to that, but “natural talent” is the correct term.

I think something like “decided” feels more natural.

You would need another word after “to assist me”, such as “in” (like I’ve suggested), or even “with” (“to assist me with passing this interview”)
I can see the confusion though because if you had used “help” instead of “assist”, your original sentence would’ve been correct.

By the way, the reason why I was so self-confident towith it is that there awere only basic English requirements.

“Why” by itself would imply that you’re posing a question, which you aren’t, so “the reason why” would be more accurate.

“Self confident” is ok, but I feel that the “self” part is a little unnecessary here, and also makes it all more wordy (but this is only personal preference).

“To” —> “with”
You would be confident with or in something, not to something.

“Are” —> “were” to keep the tense consistent.

So just good luck to me!

“Just” feels unnecessary here.