How to make a private teleporter and how to connect multiple place's stats into 1?

Hi! I'm making a game that has many game modes in it. And I'm wondering how I can make the teleporters private like the game Camping, in the game camping there are private teleporters. I can prove this by going in a game in the Lobby and seeing on the homepage if I joined the teleported game. And it does not. I am wondering how to do this so I can teleport players into the game modes without going to the game mode homepages and actually playing from there, I want them to join the Lobby so they can join the game modes. Also, I heard there is a way to connect the stats when using a private teleporter. For example, if there were only 58 people playing in the Lobby and 100 playing the teleported game then it shows on the main lobby homepage that there are currently 158 people playing. I heard it has to do with something about StarterPlaces. Please let me know how I can do these by mentioning a script with steps. Thanks

I suggest you read this: https://developer.roblox.com/en-us/api-reference/function/TeleportService/ReserveServer