How to get a Gamepass to...?

I want to make a game pass give health when bought, how do I go about getting this to work? Do I make a "VIP" room that has a health giver? Or is there a script that I can use that does this as soon as the player joins?

"Or is there a script that I can use that does this as soon as the player joins?"
No. Learn to script.

You'll need PlayerAdded to get when the Player joins the game. You'll also want GamePassService to see if they have a pass.

If they have a pass, get their Player.Character.Humanoid and give them extra MaxHealth.