ナンバー２ (I would say: 2番目のノート)

だから、私は日本語を勉強することをが試しています。

*I think you wanted to start with "So..." but in this case it's not necesary in Japanese. If you want to add something, saying ええと、is better. 

日本語の文法はが難しいです。

*If you started with the formal form like 試しています, with ます/ です, it seems sophistcated using the same form, in this case 難しいです, with です. 

英語とはからとてもまったくちがいます別なですよ！

"A is different from B" = AはBとは違います/ AはBと違うものです

"totally, completely" = まったく or ぜんぜん in this case

Good job! I understand you. Yes, as you said, our languages are different from each other, so learning English or other languages is very difficult for us, too. Please enjoy learning Japanese. I hope this helps you. ¡Saludos!