Scarleteen

I've read online from many different places that porn isn't what real sex looks like, and that it's just for entertainment. That got me wondering about what happens in real sex and how do you figure out what position and stuff you are going to do.

That's a very big question, including because what sex is like with people is almost as diverse as the billions of people who exist!

That said, I'm going to toss a few links to a couple articles that can get you started on some of this, answer the specific question you asked here, and show you some things that are or should be part of sex in real life that usually aren't in porn or aren't shown in porn. We can talk more about all this after you check those out if you like!
• What Makes Someone Good in Bed?
• When Sex "Just Happened" (And How to Make It Happen Instead)
• Driver's Ed for the Sexual Superhighway: Navigating Consent
• Left Foot, Red, Right Hand, Green: The Deal on Sex Positions

username wrote: it's just for entertainment

real sex is also an entertainment
and there are no strict rules. if you and your partner want it, it may look exactly like porn

Except probably not, still, because almost all porn is very highly edited.