How does selling a Crypto work?

I'm always confused about the selling part of the options. I know that if you need to buy or own a crypto, one has to sell it you or you'd have to mine it yourself, but when it comes to the selling part I'm confused. When I sell my crypto what happens then, (¹)is someone (or a lot of individuals) buying it at same time? or (²)am I taking the money from the already existing liquidity pool? or (³)a combination of both of these. I thought if it as the first one(¹) and was satisfied with it until i finally understood the "rug pull" scam, which wouldn't be possible without the second part(²) or the combination of both(³). Someone please explain this stuff. Is it same for the spot, margin and future option?