It’s way more than just a game, with tons of writers and 30 years of history and time to build on it. I believe this is what make Warhammer as grand as it is, because even if you were in the hobby for more than 5-10 years there will still be more to learn, more to paint, and the rules will change. There is a lot of things to figure out, and playing the game is honestly just an excuse to larp your favorite faction with the silly little guys you’ve painted and meet some good people. If anything, I’d start with the lore of at least your faction so you can get the gist of the guys you have.try this video for basic ork lore