OnlyFans is generally a porn distribution platform, yes. It was created with wider intent, but was taken over by amateur porn makers. You basically sign up for free, then you subscribe to people you wanna jerk off to or whatever. some accounts are free, some are paid, most offer paid content on the side, like custom requests or old videos. I help one of my friends make content for her OF account here and there; I'm happy to answer questions you have about it.