"Frame" is not a valid member of ScreenGui. Please Help me with my Error?

script.Parent.MouseButton1Click:Connect(function() script.Parent.Parent.Frame = false end)

You're going to want to use Locals. Is the script inside of the button? Put the script into the ScreenGUI, define the button and frame and ensure that it is localized correctly.

local button = script.Parent.TextButton
local frame = script.Parent.Frame

function Click()
	frame:Destroy()
end
 
button.MouseButton1Click:Connect(Click)