improvement and overcoming loses

So from the moment i played i knew i wanted to be good so i tried hard every game for 500 games on my first account to get a better understanding of the game on this account that i use i did just for ranked and to improve, i did my placements 2 weeks ago and went 5-5 to get silver and then i came back to ranked to play and since yesterday have been going on a massive L streak in both ranked and normal's. Usually loses dont affect me if i did my part but just wasn't able to transfer any lead i had to help my team win but every game i played a massive part in the loss . I rewatched every game and compared it to a high elo adc and my positioning is horrendous i dont have high CS, my damage is minimal. i could really use any advice ill even link my op.gg

http://euw.op.gg/summoner/userName=0utlier

I would also like some information on when to play Ezreal and lucian and caitlyn or twitch and How i could practice kiting