no 1 game will be the answer.

I would say you need a proper 4 game lineup to be able to practice.

1 EM (Pick something good with a variety of shots and full size flippers because most games you will play on will be full size flippers)
1 Classic Bally class of 81. I would say EBD because it is the tops of pure pinball for scoring purposes
1 90s DMD. I would say Jackbot. It is one of the best, if not the best for standard 2 flipper layout with variable ball speed and great risk v reward with 2 main scoring strats that are well balance.
1 newer Stern because that is what you are going to see alot of. Lots of Sternaments. I personally would pick something you like but would say games like SW/GOT are good for math/think on your feet play style. TWD is good for lots to do. Maiden is good for 4 flipper and you will want practice on a more than 2 flipper game.