What’s up with the R-rated movies? Does an adult have to watch the movie with a teen or can the adult just buy a ticket for them?

No, an adult should accompany a “child” under age 18 to see an R rated movie, especially on a Friday night. Teens who are there just to “hang out” are quite disruptive without adult supervision

I have no idea. I always went with my child

It depends on your age bracket and what movie

Just call them and ask