Open script
script.Parent.MouseButton1Click:Connect(function()
	game.Players.LocalPlayer.PlayerGui.Gui.MainFrame.Visible = true
	game.Players.LocalPlayer.PlayerGui.Gui.Open.Visible = false
end)

Exit script
script.Parent.MouseButton1Click:Connect(function()
	game.Players.LocalPlayer.PlayerGui.Gui.MainFrame.Visible = false
	game.Players.LocalPlayer.PlayerGui.Gui.Open.Visible = true
end)