Shrink then get bigger gui script doesn't work?

So i wanted to make a GUI, if you touch it, it will get smaller until your screen is black, and then after some time, it will get bigger again.

So i honestly have no idea what i am doing and i don't understand the wiki

could someone teach me how this stuff works? or help me with it.

Script (like this is made by an enourmous noob)

script.Parent.Frame.Position = UDim2.new(0.5, 0, 0.5, 0) 
script.Parent.Frame.Size = UDim2.new(0,0,0,0)
script.Parent.Frame:TweenSizeAndPosition(UDim2.new(0, 400, 0, 600), UDim2.new(.5, -200, .5, 600), "Out", "Quad", 1)