lLangcorrect

Should start with a capital letter.

I’ve started “Langcorrect” since two days ago.

'simple tense' - statement of fact, completed, past. Do not need 'since' and since would go with a date not an amount of time.

I made many mistakes but the people who corrected the sentences were so kind.

Specific group of people to definite article. Past tense of corrected. Specific set of 'sentences' so definite article needed.

They kindly corrected my worsebad English kindly.

Put kindly near word it describes and you only need the basic adjective 'bad' not the comparative form 'worse'. You could also use 'terrible'.

I was glad because I could learn righcorrect and useful English.

'correct' not 'right'.

Sometimes, I find other people’s worse Japanese sentences. terrible. However, I can’t correct them because I’m afraid that my Japanese may be worse.

I’ve started “Langcorrect” since two days ago.

I made many mistakes but the people who corrected my sentences were so kind.

I was glad because I could learn righcorrect and useful English.

ThenStill, I will try as hard as possible.

I’ve started “Langcorrect” since two days ago.

I’ve made many mistakes but people who corrected sentences were so kind.

They corrected my worsebad English kindly.

Worse is when you want to compare, “this is worse than that”

I was glad because I could learn righcorrect and useful English.

Sometimes, I find other people’s worsebad Japanese sentences. However, I can’t correct them because I’m afraid that my Japanese may be worse.

lLangcorrect

Make sure to capitalize the first letter of a word in your title.

I’ve started “using Langcorrect” since two days ago.

Use "I started" instead of "I’ve started" because you're referring to a specific time in the past ("two days ago").
"Since" isn't needed here, as "two days ago" already sets the time.
"Using Langcorrect" makes it clearer that you're talking about the platform

I made many mistakes, but the people who corrected my sentences were so kind.

Added a comma after "mistakes" for clarity.
"Corrected my sentences" sounds more natural than "correct sentences."

They kindly corrected my worsepoor English kindly.

"Poor English" is a more common way to describe English that needs improvement, rather than "worse English."
"Kindly corrected" sounds more natural than "corrected ... kindly."

I was glad because I could learn rightproper and useful English.

"Proper" sounds more natural than "right" when referring to language usage.

Sometimes, I find other people’s worseincorrect Japanese sentences. However, I can’t correct them because I’m afraid that my Japanese mayight be worse.

"Incorrect" works better than "worse" when describing language mistakes.
Added a comma after "however" for correct punctuation.
"Might" is often used when talking about possibilities, like the potential for your Japanese to be worse.

ThenBut I will try as hard as possible.

"But" works better here as it contrasts with the previous thought.

lLangcorrect

I’ve started using “Langcorrect” since two days ago.

I made many mistakes but the people who correct sentences were so kind.

They kindly corrected my worsepoor English kindly.

I was glad because I could learn right andcorrect, useful English.

Sometimes, I find other people’s worsepoor Japanese sentences.However I can’t correct them because I’m afraid that my Japanese may be even worse.

ThenStill, I will try as hard as possibleI can.