I’m kinda coufused, are they on an actual school? Did I miss something????

The place is an actual school but it's not a regular one. This is a program on graduation with participants coming from student age but did not finish school, whether because of becoming celebrities or quitting the school for personal issues like bullying and so on so that they can enjoy the feelings of graduation. The participants were screened by the production team to ensure noone was quitting the school for bad reasons Ike involve in crime and so on.

But...

As always, there's always that bad guy and I bet you can guess who he is.