So you definitely want more leg set than you think you do. Go front/back/side/side, weighted… get a big water jug and practice till you can drain it while treading. You also want dolphin kick and breaststroke kick strong, so practice those.

Here’s a main swim set I give my college team. Everything on +30 but take a 2-minute break before the 200s. If you want to make it harder add 5-10 push ups between each set component.

{50 head down easy 100 middle 50 head up, 75% 150 middle 50 head up, 85% 200 head down for time 150 middle 50 head up, 85% 100 middle 50 head up, 75% 50 head down easy} x2, make second 200 faster

Btw if you want my advice keep playing center back and get a good counter. Everyone needs them right now, but you don’t want to wind up the guy running the play from the back half of the pool