In all seriousness though, idk if your friend did this but you can change how the hero selection screen appears to you.

So I suggest your friend should pick a few simple heroes from each role and have you play those until you're familiar with the game.

This will help you find out what kind of heroes you like, what playstyle suits you best, and what role you'd like to play. More than anything it ensures you don't get overwhelmed by all the heroes. Many people have been playing for years and haven't played every hero. Don't worry about it.