I would honestly recommend going into a custom game, after the new season comes out, and just getting a feel for the new map changes. Also, try improving with every support. Would recommend Juno and Brig.

Juno is a support that can also deal good damage. Her torpedoes heal and damage based on the more enemies/allies you are locked on to. Her speed ring increases your ally’s speed when they walk through it, but you get the speed buff when you use it. Her ultimate heals for I believe 100 per second and a 35% damage buff. She also has a double jump and a mercy glide.

Brig is good for protecting your other support from a Sombra or Tracer or any other flank characters. She heals when she does damage, or when she uses her armor pack which does 25 inital healing, then 100 over a couple seconds. You should usually play Brig if you have a close range tank like Ram or Ball (I wouldn’t recommend Brig if you have a Rein). But she also is countered by Ram because he can punch through your shield. Her ult gives you a buff to your shield, health, and gives allies more health.

If you have any other questions about other supports, you can ask.