I want to make it so a player have 3 different save slots they can use, and I know the concept - having 3 different keys to load and save. However, my problem is, how would I send the information to another place since there will be a teleportation.
For example, in a starter place, a player chooses Slot2, how would I make it so once they get teleported, they use Key_2 to load in the game?
As stated in the documentation, the handling of teleportData being sent to the destination place server is done by the player client, which means it’s at least theoretically possible for something wrong on the player’s side (including interference by exploiting) to result in invalid/spoofed teleportData received by the destination server at which they arrive. Although this shouldn’t normally happen, it may still present a security issue in certain cases.
Therefore, one should implement error handling at the receiving end. Also, generally only use this for transmitting player preferences such as which save slot they selected at the starting place’s menu, and avoid using teleportData for any critical information such as communicating player stats and money, as this could potentially be tampered with as mentioned before.
A more complex (and secure/reliable) alternative to teleportData would be using a Memory Store, although in your case this would not appear necessary.
A secure but probably less reliable alternative for communicating data between servers would be MessagingService, though this is meant for less crucial uses such as making a global announcement.