Which Linux Distribution Should I Choose

Hi mates! I know that this is very popular topic and I can find many answers on google, but I want to know your opinion.

BTW: Sorry for my English, I am not natural speaker. I hope you will understand :D.

I am 17 and I have MAC OS X. That means that I am little bit familiar with all those commands in terminal. I have some basics of C (I have ended with pointers - including them) and Python (OOP-not yet). I want to buy myself a Raspberry PI 3 and start learning Linux from scratch. Before moving to Kali Linux or other distributions for OG users I want to choose something familiar, but not too much. I want to use my terminal most of the time (because you know, best way how to learn is practice). That means that probably not Ubuntu. But I am not familiar at all with all other distributions of Linux among the internet. Can you help me?

I will be glad for every reaction on my post.

Can you please also rate my English? From 0 to 10. 10 is best. Thank you so much.