Hi, this is very good! But there are some minor mistakes. Here are my corrections:

First notebook entry: Introducing myself

I'm learning English, because I want to study abroad. - In English, we don't put a "," in front of "because". Also, I made two sentences of your long one. It reads better this way.

I love learning languages, and it's a good opportunity to make new friends too.
I'm speaking Hungarian, and I grew up in Hungary. - "I'm speaking Hungarian" means that you are speaking it right now. I guess you want to say that you are a native Hungarian speaker, so we use Present Simple here: "I speak Hungarian" (this is the state of things rather than your activity at this moment). And there was an extra "," again.
I enjoy playing basketball and volleyball. I love to programming, I'm learning it almost constantly, and I'm good at it. - It's better to say "I love programming". Programming is a noun and it just sounds better here. If you say "I like programming", you are telling us that you like the subject and not just the activity.

I often go to programming competitions.
I like reading good novels, like Flowers for Algernon or Hunger Games.