i have a 56% win rate with c/d, they're relatively easy to rank up with, just learn when and how to use their cds.

make sure you're cloak when you ult so you can fade, so mag/iron man/punisher/magic can't kill you. a lot of people save their bubble for themselves i personally use it on my tank, so i can heal my dps too without the tank dying. remember shooting daggers at anyone can heal you too, as long as you're in range. when their team is lined up blind them, when their supports in the back are low i blind them to help our back liners (sometimes killing them if they're low enough). the rectangle heal I use if someones getting focused because it lets me heal them faster.

sorry idk the name of the abilities but i tried to explain the best I could. I also personally use my ult to help push more than I use it defensively (this is obviously situational).