Please ensure your post follows the Scripting Support category guidelines in the future. Your post is vague and doesn’t properly address the necessities of a help request. Don’t state your error and then post your whole code: help us through with information and addressing what you’ve attempted first.
That being said, look at your console carefully and address the problems. The main issue is that your function, Movement, is only declared in the scope of the function connected to MouseButton1Click of your GuiButton. You’re trying to connect a function out-of-scope that doesn’t exist.
Move the function out of MouseButton1Click.