5% Royalty

I’m currently making my own officials website where i woulde sell my games that were making. How does this 5% loyalty works. Do i give 5% of every money that i make with my games to epic. What if the game is free

@Supergamer & KitatusStudios thanks for this thread and for the answer. I’m a newbie and i already have a solid platform for my game however im looking for a game engine that is not too greedy and have a wide community with ofc newbie friendly environment. I think Unreal Engine is the perfect game engine for me and my project.