How can I make a GUI that has gamepasses inside?

So, basically what you want to do is make the frame, and have all the gui buttons in them. Then, you put this LocalScript in each button:

local plr = game.Players.LocalPlayer
local mps = game:GetService("MarketplaceService")

script.Parent.MouseButton1Down:Connect(function()
    mps:PromptGamePassPurchase(plr, 12345) --Change 12345 to the id of your gamepass.--
end)

This belongs in a LocalScript. Not a regular one.