The best advice I could give would mirror Moonbeam's: try as many different types of systems as you can. Try games meant for combat, games meant for social drama, games with horror and insanity consequences, games with intriguing magic systems, d20 games, d6 games, dice pool games, fate dice games, those crazy star wars ffg dice... try a bunch and see what you like.
Then figure out what kind of world you want to play in, and what kind of stories you want to communally tell. That can help you narrow down the system you want to use pretty quick.
Do you want to roleplay the political tension of noble houses trying to out maneuver each other in a bid for the throne? Sure, you can play it in any system, but some systems are designed specifically for that style of play (A Song of Ice and Fire RPG springs to mind) while others might not have as detailed rules for every type of conflict. Your system has to have the right moving parts. You could play all that political maneuvering in 5e, but the single roll social conflict resolution might be unsatisfactory.