iImproving eEnglish

Generally, all words in a title are capitalised.

HELLO tello! This is my first text.

Making an entire word capitalised gives the sense that one's shouting very loudly. You may consider an exclamation mark so that it is more toned down.

I study for my englishEnglish, for it will be good for medical school.

This is an advanced grammar structure, and might sound literary at times. Here, "for" means "because" or "since". Of course, you can always replace it with another word: "I study English since it will be useful for medical school."

Because tThis year i, I will get started in the medical faculty, but unfourtanunately this faculty just learne lessons are only taught in eEnglish and my eEnglish isn't good enough for it yet.

(1) I reworded your sentence while fixing some grammatical errors, so that it sounds more natural and flows more nicely.
(2) I felt that the "because" at the start was unnecessary and perhaps an awkward transition from the previous sentence, so I removed it.
(3) The pronoun "I" should always be capitalised.
(4) "English" is the name of a language, so it's a proper noun and should be capitalised.

I knowcan reading a e an English text and answered multiple choices questions but iI'm not good at listening or writing.

(1) "English" starts with a vowel sound, so you should use "an" before it.
(2) The phrase is "multiple choice question" (the "choice" is singular).

I am watching ean English series.

tThesey are himymHow I Met Your Mother (HIMYM) and pPrison bBreak.

(1) I'd suggest spelling our "How I Met Your Mother" in full for the benefit of readers who do not know the abbreviation.
(2) "Prison Break" is the title of a series, which should be properly capitalised.

But iI haved to watched with subtitles.

(1) "Have to watched" is ungrammatical.
(2) In this context, "subtitles" should be plural.

Anyway.. i.I liked it :) ¶
Do you know the Turkish educational system?

In the same way we capitalise "English", we also capitalise "Turkish".

iI am sure you have heard of it.

The phrase is "hear of (something)".

iI studied for two years with dicipline and seriously.

Your sentence is actually grammatical, but alternatively, and perhaps more clearly: "I studied seriously for two years with discipline."

But even after all i canthat I could not go to the university iI wanted.

Mind the tense. This is something that occurred in the past, so the past tense should be used ("could", "wanted").

Improving my eEnglish wasn't in my plans.

aAnyway, there's nothing to do.

Here, a comma is typically placed after "anyway".

That's all..

Strictly speaking, ellipses should contain three dots ("..."), but for informal and more personal styles of writing two dots is fine. Two dots does feel more friendly. (Use three dots in formal writing though!)

iImproving engmy English

HELLO this is my first texpost.

I'm study for my english will be good foring English to work in the medical field.

(medical school?)
(medical work?)

Because tThis year iI will started work as a medical facultyility, but unfourtanunately this faculty just learn in eility only uses English and my eEnglish isn't goodquite good enough for it yet.

I knowcan reading a e English text and answered multiple choices questions, but iI'm not good at listening or writing.

I am watching english series.-

these are himymI'm watching two shows in English: HIMYM and pPrison bBreak.

We can combine this with the previous sentence. Also, for abbreviated show titles like How I Met Your Mother, we typically use all capitals

But iI have to watched with subtitles.

Hopefully they're English subtitles! :)

Anyway.. i. I liked it :) ¶
Do¶
Are you know tfamiliar with the Turkish educational system?

i aI'm sure you've heard of it.

iI studied seriously for two years with dicipline and seriously.

Both "seriously" and "discipline" is a bit redundant. Another option: "I studied diligently for two years."

But even after all ithat, I cannot go to the university iI want.

Improving my eEnglish wasn't in my plans.

aAnyway, there's nothing to do.

That's all...