The Dream

I've been playing League of Legends for about 2 years now. I've been putting in massive amounts of time into the game. Probably about 70-80 hours a week. I'm been telling myself that I'd go higher than my friends, because they said that I'm bad at the game. I just want to prove them wrong. I want to get to Diamond, or even higher. My current rank is Silver 5, 67 LP as of 6/13/2017. Can anyone high ELO (Platinum 1 and Above) coach me about what I do wrong, things to work on and etc? I'd appreciate it :)