We are playing Pathfinder first edition from Paizo: https://paizo.com/pathfinder

Not to be confused with second edition.

The first edition is noteable for being able to use all the (many, many) expansions from 3.5 edition of Dungeons and Dragons. You can read more on the Wikipedia: https://en.wikipedia.org/wiki/Pathfinder_Roleplaying_Game

As for all the details, they are practically infinite. My wife thinks I'm crazy to do so much work for a game. But the end goal is having fun, and it is actually quite fun, once you know what you are doing. Much like any other game - learn the rules, and play within them.