How exactly do you make a GUI appear on the press of a plugin button?

I've tried cloning it to the CoreGui, I've tried making a new GUI inside of the clicked function,

openUIbutton.Click:connect(function()
local gui = Instance.new("ScreenGui",CoreGui)
Instance.new("TextLabel",gui)


end)
                                                                                               ]]--

Not entirely sure what to do from this point on, if I manage to get this working, do I need to use remoteevents to do serverside stuff? (because i'll obviously be using a localscript for the gui, no?)