It's all about the cue ball
Put aside fundamentals, aiming,sighting,bridges,grips,,this shot that shot,and anything else that can be taught in this game, IT ALL COMES DOWN TO STROKE.
You can be a walking encyclopedia, what good is it if you can't perform it.
Combine stroke with everything else and you have a chance.
There are great players that are like watching a train wreck at the table until you see their final delivery stroke.
Find someone that combines book knowledge and can teach stroke, and actually perform the strokes and all the variations of each one.
Other than that what Blackjack Said...Straight Pool,, I would add billiards to help along.
Pool is all about the cue ball. The other balls on the table are these pretty colored things you play with while you play pool with the cue ball.
Best of Luck