Staking question

Considering staking my small bag of cardano but I am unsure how the fees work. If the fee is 2% plus 340 ada, is that taken from the total rewards at end of epoch or is does it cost everyone 2% and 340 ada each epoch? Also, is yorio a good way to start? Probably a stupid question but hoping you guys can shine some light on the subject for me. Edit: Thanks for the helps guys, I'm starting to understand the idea of staking and the fees behind it. I'll do abit more research and will hopefully be joining a pool soon.