I went differenttook various English courses many years ago. / I have been taking various English Ccourses longfor many years. I took various English courses many years ago. / I have been taking various English courses for many years.

I am not sure of the intended meaning

They said ; y, "You are level C1." They said, "You are level C1."

This is American English punctuation. British is slightly different

But I don't think thiso. But I don't think so.

This is more common usage

I need some practice, with listening and so muca lot of practice with speaking. I need some practice with listening and a lot of practice with speaking.

I need someone forto improve my speaking. I need someone to improve my speaking.

I hope you can/will support me. I hope you can/will support me.

Cause ı need to my wrongmy incorrect sentences to be fixed. Cause ı need my incorrect sentences to be fixed.

"Incorrect" is the standard term used to refer to language learning or grammar in this context