How to study well in English?

These days/Recently I watched some English videos, and I realized why I couldn't get better in English, although I have been learninged it for a long time.
Before, English was a compulsory subject with/for every student. I was always afraid that i'll I would be wrong if I speak English. I was afraid to pronounce, of the grammar, and I was almost unable couldn't to listen. I was afraid in of everything.
(These days) I watched some English videos, and the teacher said/told me that "if you want to study well in English, you have to make mistakes". Maybe when I speak, a foreigner can understand,  but even if it's not good with well-pronounced, with mistakes in grammar, and so on. So, I am trying to write every day, and I hope I can get better from by doing this these notebooks.

It's an axiom* in language learning that  'we learn by our mistakes', but this only applies if you take note of the corrections, and avoid making the same mistake again.  Don't worry about making mistakes,  but try to learn from them.

*widely-accepted idea

How to study English well?

These days I have been watching English language videos, and I realized why I am not speaking English better although i have been learning it for a long time.
Before, when I was in school, English was a compulsory subject. I was always afraid that I would make mistakes when I spoke English. I was afraid to say anything in case my pronunciation and my grammar were wrong, and also I could hardly understand anything. I was afraid of everything.
These days I have been watching some English videos and the teacher in the videos said "If you want to study English well, you have to make mistakes." I think that when I speak, foreigners can understand me, but my pronunciation, grammar and so on are not good. So, I am trying to write everyday. I hope i can get better from writing in Notebook.