This doc goes into how to setup the New Input System in Unity 6.3 and use it within code...
The old input system and New Input System are very different and both have pros and cons. The New Input Systems main pro is that you can easily setup many different types of controllers for the same actions, that said it's more complicated to setup than the old system, so that is what this doc is for.
The New Input System works by defining key references for actions in a game, like Move, Jump, or Select, rather than referencing the controllers themselves. You code for the actions, rather than the controllers, and then add controller types to each action with very little effort.
Actions can be put under different Action Maps, such as actions when using the UI, actions for base combat, actions for driving a car, whatever categories you want to create.
Action Maps can be overlapped if you want, but generally it's a good idea to keep each Action Map separate.
