In Minecraft there are different dimensions you'll need to explore to progress the 'story' of the game. It is very common in multiplayer that the server staff want to restrict entering those dimensions because of (1) slowing down story progression or (2) not being designed to have enterable dimensions, a custom build server for example. For that, I coded this Data Pack which restricts players' access to the other dimensions by teleporting them immediately back after they try to enter the dimension. It also supports custom dimensions! Coding this was my first dive into making modifications for a game, which made the process both challenging and really exciting.