Do all slot has different RTPs?
I thought they had the same, which is higher RTP compared to other games.

AFAIK, pragmatic play slots have an RTP between 94% to 96% which I think you will be able to manage how to win against the house edge.  Sugar Rush and Sweet Bonanza are the best slots that make me fun, the colors look good, which makes me enjoy the game.

Slot games are based on luck games, don't expect too much profit from them.