The only to get better is to just play the game. You can watch pro players stream, and get some tips.

Watch streams and play the tutorial. Then play Co-op vs AI. You will catch on soon enough. As an ex-league player I will admit there is a lot to learn though.

Muse wrote Watch streams and play the tutorial. Then play Co-op vs AI. You will catch on soon enough. As an ex-league player I will admit there is a lot to learn though.

which champion would you recommend?

I would definitely recommend just keep playing the game, especially knowing how toxic the community is, just ignoring them. I can see how the community can shy people away from the game. For a champion, I recommend just easy to play like Annie. Annie is an excellent starter champion, every time you use 3 abilities she gains a stun on her next damaging ability. On top of this, you can also watch the World Championships this year. Yesterday, we had two of the best teams play some of the "best" league of legends you will ever see, so I HIGHLY recommend that you watch that.

MattXO wrote

Muse wrote Watch streams and play the tutorial. Then play Co-op vs AI. You will catch on soon enough. As an ex-league player I will admit there is a lot to learn though.

which champion would you recommend?

It depends on your play style. Once you figure that out then that will determine your lane. Top, Mid, Bot (ADC/SUPP) or JG

Top is Sustain champs.
Mid is Magical bursty champs
Bot is ADC (Attack Damage Carry) Ranged champs.. Supp is tanky or supportive champs
Jung is typically a tanky or bursty champ either magic or attack damage.