Can somebody please explain to me what exactly is Scientology? - eviltoast

Daughter and this classmate of hers have been dating since August. She told us him & his whole family are Scientologists. I’m not going to lie, I didn’t know anything about it until she mentioned it, my first thought was “oh, they believe in science? That’s cool”. Then I looked it up online… and I still don’t understand anything. Most sources say it’s a bad thing, but I don’t get what it’s all actually about, as in doctrine, beliefs, activities, etc. I don’t even understand if it’s an actual religion or one of those pay-to-level-up self-care courses. One of the most confusing things I’ve ever read about. So if anyone could explain it straight to the point, I’d be very grateful.