How do you use ModuleScripts?

Basically, a modulescript doesn't operate by itself. Think of it as a library. You must have a separate script(not modulescript) that utilizes it.

The way a modulescript works is interesting. Though I won't go into that, you should learn more about it. Just know that for every module script, you must a table that contains everything in the module script and return it.

Here's an example:

ModuleScript:

local lib = {}

function lib.sayHi()
    print("Hi")
end

return lib

Script:

local myModule = require(workspace.ModuleScript)
myModule.sayHi()

Output:

Hi