You didn’t provide much information (I don’t know what page 47 of the “godot.pdf” is), but you are either using get_node() with a node that doesn’t exist, or trying to create an instance of a nonexistent node.
I see what I did wrong. First off I meant to say that I was following along in the Godot docs > getting started > scripting continued > processing section in the step by step section that introduces scripting. One of the problems was that I had accidently created the button as a child of the label instead of the child of the panel. So when I went to use the GUI to connect the button to the pressed() signal, I chose the wrong path and the engine didn’t find what it needed.
Secondly, I had used the GUI to connect the pressed signal with the button control and THEN when into the panel script and connected the two again. Thus creating a debugger error that said I had preformed the connection twice needlessly.