Could you please help me and correct find out the mistakes of these sentences

This is my the first time I have written in the Notebook. to write papers here,I have just passed the test of CET-4 test. I do believe that practice is the way to get success, so I keep going. I learn about 20 new words everyday and revise them.
But you know, no matter how many words you have already learnt remembered, you still can't speak fluently with foreigners English speakers from around the world. I think it's a big problem for many freshmen.
Learning a new language, and learning know about another country's culture, some day you will change the way you think about the world.

Could you please help me find out the mistakes of in these sentences

Please note:

If there is a more natural way to say something, I have written it down inside parantheses right by your original sentence.

freshmen: first year students in college so you wouldn't use it in this context.