Quite frankly, learn Annie, Ryze, Miss Fortune, and so on. While you learn the game, it is best to focus on champions who require the least skill to play at a reasonable level. All this really means is stick with champions with easy builds and few (few = none) skillshots.
In my opinion, Annie is the number 1 best champion to learn the basics of laning because she is really easy to learn (farm with your Q), relatively safe, high damage output without gold (it won't matter if your cs is lacking), and she can be played in multiple roles (Mid, Top, or Support...and Jungle for the daring :D )
At a level lower than high gold (gold 1 50lp ish), the most effective use of your study/practice time is done by yourself in custom games, BUT--you can't level an account that way, try to play as many normals as possible. Remember, you aren't playing to win, you're playing to make a ton of mistakes and learn from them.
^ This is the best way to level an account. If you want the fastest way to level an account, get an X-time EXP boost and grind out ARAMs (but that can be boring and you won't learn anything about the game)
A pro has made more mistakes than an amateur has attempted
Although Kayle fits the previously mentioned criteria, she has recently been nerfed, so she isn't as effective as Annie (or Ryze). Also, the benefit of someone like Ryze is he get really tanky as he builds damage, so he can burst down a team with heavy AoE AP damage, while being relatively hard to kill.
To conclude, what I advise you to do would be to save your IP for tier 3 runes (once you hit lvl 20), pick up Annie and Ryze, and play them in as many normal games as possible. Keep in mind if you play poorly you might get flamed, but just remember everyone was new/weak in this game at one point, it's alright to make mistakes, and "/mute all" is your friend ^.^
YT: /tboi3000
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