Hi. I have been studying English language (specify the time "how long have you been learning" or use another tense), but I know it's bad (it's not clear what "it" means here: sounds like it's bad that you learn english =) ). I would be very happy if you help.

I would say:

I have been learning English for 2 years, but still I can't speak it. I would be happy if you help me. 

 or

I'm learning English, but it's hard for me. I'll be happy if you help me.

First notebook entry: Introducing myself

Hi. I have been studying the English language, but I know this is bad. I would be very happy to help.