I just want to practice a role but have to dodge and wait 15 minutes every time I get secondary

what you do is put mid as your secondary role. If you want to practice mid, then you are SOL

takes 1 - 2 hours to get through all the dodging and champ selects just to play a game that is so catastrophically imbalanced by matchmaking that it's an unsatisfying 15 minute open mid experience

another fine job by the experts at riot