How many bans before a perm ban?

Hello, so I recently got a chat ban and wanted to talk a little bit about it. I have always been really careful about my league of legends account...it's the only one I play on and I really try to take a good care for it. I started playing league at the end of 2015, got addicted to the game and that continued to sometwhat the begining of 2017, than i took almost a 1 year break. A few months before I took the break my cousin started playing league too and I was trying to teach him...he got amazed on how many champs league has and he wanted to try them all and luckily because of my addicition I had the majority of them ( sorry for going so long, hold one I'm almost there). So he requested to play with my account...we are really close cousins and we do trust stuff to each other so of course I letted him, before I took the break I told him he could play as much as he wanted just not to change the name or stupid stuff. I start playing again at begining of 2018, I talk to him...i'm like what's up and he had got decent to the game now and stopped playing with my account and trying to improve his one. During the break I sort of breafly heard what the new honor level were but did not really get into it and when I got back I realised that I was lvl 0 dishonorable, I knew you started with level 2 and no idea what happened there so I moved on and thought I would upgrade it. But it was pretty difficult and after a while a sended a support ticket to riot to ask what is going in. They said that I had gotten a 14 day ban and therefore my levels we're locked. I talked to my cousin and he finally commited that he had done it. I also got the information that account sharing is a restriction and I got a warning for that in the ticket and I totally agree. Now after all that stress everything was fine until today. Now is the end of the school and even though I am a good student I have my problems too and thinking that league would help me pass that I actually reflected into it and got somewhat toxic the past few days and today I got a 10 day chat ban. P.S so sorry for going this long, just wanted to share it all, dunno why.

Now I've heard from some friends that if you get 3 bans the next one is perm. Now is this true and if it is does the chat ban count? And last thing...if this is some sort of youtube copyright strikes do the bans actually get removed after a specific amount of time if you improve your game?