How do i detect when Player clicks but not on gui?

For this you'd have to use UserInputService, though you'll have to use InputObject.UserInputType to get the Enum path for Click-Input. The reason behind using a different Service is because this particular one passes the GameProcessed Bool that allows us to primarily reject Click-Input from ClickDetectors and GUI's

UserInputService.InputBegan:Connect(function(InputObject, GameProcessed)
   if (InputObject.UserInputType = Enum.UserInputType.MouseButton1) then
      if not (GameProcessed) then
       print("Player Left-Clicked")
      end
   end
end)

It's a simple as that.

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