How to fire a module script as a function from a script?

I didn't know how to say it as a question but I'll explain it here. So I am making a surface GUI with a customization feature to change the color of the surface GUI when clicked.

What I'm trying to accomplish is to make a function in a module script to avoid the pain of copying the script in each individual colors in case I have to make a change to the script.

So here's the module script:

-- The main Frame of the surface GUI to change the colors
program = script.Parent.Parent.Parent.Parent.Parent 

return function()
	program.Menu.Titlebar.BackgroundColor3 = script.Parent.BackgroundColor3
	program.Screen.Settings.Titlebar.BackgroundColor3 = script.Parent.BackgroundColor3
end

and here's the script that's in each button for the colors

local ColorChange = require(script.Parent.Parent.ColorChange)

script.Parent.MouseButton1Click:Connect(function()
	ColorChange()
end)

Its the first time I have tried to use ModuleScripts so help would be appreciated. I don't know if I have explained it properly so feel free to ask.

You can do it like this

ModuleScript

local program = script.Parent.Parent.Parent.Parent.Parent

function module.ColorChange()
	program.Menu.Titlebar.BackgroundColor3 = script.Parent.BackgroundColor3
	program.Screen.Settings.Titlebar.BackgroundColor3 = script.Parent.BackgroundColor3
end

Script

local module = require(script.Parent.Parent.ColorChange)

script.Parent.MouseButton1Click:Connect(function()
    module.ColorChange()
end)