How would I make a gui morph button I have knoledge with scripting but not this subject?

How would I write a function inside a local script to morph me into a model with guis.

local screenGui = Instance.new("ScreenGui")
screenGui.Parent = script.Parent

local frame = Instance.new("Frame")
frame.Parent = screenGui
frame.Size = UDim2.new(0,100,0,50)
frame.Position = UDim2.new(0,200,0,400)

local button = Instance.new("TextButton")
button.Parent = frame
button.Text = "Any Name you want"
button.Size = UDim2.new(0,100,0,50)

^ | use this to start off your Gui. You can change the sizes and positions of all Gui. Don't forget to put this in a local script in "Starter Gui"

first you manually delete (as in via script) each of the old limbs. then, I would change the names of the parts your adding, to correspond to each of the old limbs. For the torso and head, I have no knowledge of how you would change those without killing the character. This is because my method uses :Destroy(). Anyway, after removing the limbs, you must re-attach them by using a 6D motor in roblox. I believe you need to line them up with the character though. That is all the current knowledge I have, if I come up with anything else, I'll add it. =)

Hope it helped at least a little