Toxicity Help

Hello everyone, I'm not posting here because I want my account un-banned, I'm not posting here because I want to bitch about how it's unfair I got banned. I truly want help and your feedback on how I can improve my attitude. I don't want to be toxic anymore, I've tried so many times and I just still go back to my toxic roots. Let me tell you a bit of my story.

 I'm 14 years old and I've been playing League of Legends for a long time now. I've played since the start of Season 3, and I've progressively improved. As I hit puberty and I started to learn(not necessarily learn, but understand) swear words and all the curses in the book, and the combination of me getting more competitive about League, I became increasingly toxic. It got to a point where every single game I would constantly rage at my teammates and I hated playing the game but I was addicted. When I was in Bronze I legitimately thought that I deserved to be in high plat or diamond elo. Obviously, this was not the case, and when I realized this I climbed to Gold 5. I recently came off a 14-day suspension and in my second game I got mad in the first few minutes of the game and started to yell at my teammates. The basic things happened and I ended up getting permanently banned. Now I just want to emphasize I'm not asking to be un-banned and I'm not complaining about Riot banning my account, I think I deserved it 100% and I'm happy that Riot is stepping up their permanent bans. Although I have "learned my lesson", I know that I'm going to be extremely toxic when I level a new account. If anyone has any ideas or tips, please share them with me as I greatly need them. Thank you for reading this far.