Ranked draft

I started playing a lot of ranked recently and I wanted to learn how to draft. My biggest problem is knowing which brawlers count other brawlers and the brawlers good on a map. When I see other posts about this people usuallysay aomething like "you just have to play the game more to understand counters" I have played the game but I still don't fully understand them. I would appreciate if you told me how you learned to draft or tricks to draft.