One day get to top500

I am a plat tank, 2400 dps and 2400 support. However, I have lots of accounts and have played as a diamond tank, diamond dps and mid plat support. I am getting annoyed with comp and wish to play something I little more team based. I have a deep understanding of the game and strategies so I am confident I could coach but I would rather play. I have never been on a team before but play in groups as I like to communicate with my teammates. I am not sure how it works like where I would play because of my wide variation in where I play. Overall, I will most likely play support I have 50 hours on mercy and used to main her but I can flex.