Assuming you like ranged champs and you dont have a lot of points to spend i would just stick with Annie until you save up for a good mid lane like LeBlanc

If you like ranged champions I highly suggest you play AD Carry (bottom lane) with: Ezreal, Lucian, Vayne, Caitlyn or Jinx hope this helped

Try Ezreal, hes a really good champ to learn the game with.
He has everything you could need! Lots of skillshots, AD/AP ratio depending what way u wanna go, free "flash" on his E and a global ult

Okay, if you're going to want a good champion, you will need to play ALL of the free champions.
I say all, because then you can know what you like to play.

If you're into playing a mage:
Ryze. Ryze is one of the best mages on the game, let alone one very cheap one.

If you're an ADC - Basically, heavy damage range:
Ashe. Ashe is one of the most annoying champions to play against due to the amount of slowing and critical hits!

If you're a melee:
Yi. No questions, he is just really, really powerful and fun to play.

If you're a tanky person:
Alistar. He's tanky, supports his team... all while doing loads of damage!

If you're a support:
Soraka. She's very powerful for little to no reason other than insane amounts of healing. Great champion to play with!

If you like having fun:
Annie. Annie is really fun due to her ultimate (Tibbers the bear) where you land him onto them and run away... cheeky devil.

Hope this helped anyone, and if you have more questions about league what so ever, message me on here or on my youtube channel: Oheymate