There are a plethora of YouTube videos that can help you. I haven’t watched this video by TheDevKing since it’s creation so I do not know how accurate it is today. But, almost all of the information should still be relevant. As Omega77073 posted the official Roblox documentation is the best source of information but many require a visual explanation of someone doing it than just reading it.
The DataStore service is divided into two, normal DataStore and OrderedDataStore, both can save and load information that must be string, boolean, tables or numbers.
First you must “find” the “folder” of the data, this is done like this:
local DSS = game:GetService("DataStoreService")
Name is the “folder” and Scope is a subfolder in Name, Scope needs to be defined if you don’t want.
The most basic, to obtain a data use :GetAsync() and to save it use :SetAsync() and to remove it use :RemoveAsync().
There are other properties you can use like: UpdateAsync() and :IncrementAsync(). UpdateAsync: returns the old value and saves the new one you put. IncrementAsync: it only works with numbers, add the number you put in and return the new value.