How do people make a living off stocks?

I know people day trade for a living or they make money off dividends to have passive income but I’m not sure how people make a living off normal stocks. My main problem is how and when they decide to sell so that they can pay for things. Say for example you started off with a decent amount of money and invest it and get the s&p average return of ~10%. This gives them enough money after every year to live off of. (We can say somewhere around 60k or whatever it doesn’t matter really) My problem is how do they take those profits without hurting their growth year after year? Maybe it’s a stupid question but this type of idea just confuses me.