League of Legends (LoL) Question: Which champion to play If I want to learn Mid?

Annie is the traditional champion to learn midlane with. Although champions like Veigar, Malzahar, Lissandra and Twisted Fate aren't super hard either. I personally learned to play mid with Anivia, although she isn't the most beginner friendly champion.

Stay away from Azir at first in opposite to what someone here suggested (hoping he is joking) as Azir is one of the hardest if not the hardest champion to learn.

I started Mid lane with Lux and Ahri, I can recommend these two.

Xerath, Malzahar, Lux are a pretty easy start, and even perhaps Brand has a lot of kill potential at level 6.

Talon's a good pick for learning assassins mid.
Annie, Lux, Xerath, and Ahri aren't bad ideas for mage options.
Neeko if you disregard the disguise.
Veigar is a really solid one too, but it might take some time.
Vladimir also isn't that bad of an option. Never limited to these champions though!

You can't go wrong with Ahri/Lux. They have wave clear and hard cc.

I think Azir is a really beginner friendly pick with his fairly easy kit and simple gameplay

Você pode optar por Talon, boneco de roaming fácil, snowball extremo. Extremamente proativo em seus ganks. capaz de fazer os adversários se estressar ao extremo e dar FF :D

Talon if you want easier start, Heimer for opposite ;)