now I want it to where the camera with rotate only to the left or right by a press of the label button, but there is an error "cannot be used in a boolean context" any advice?
you want it to where the camera with?....What does that even mean?
Your problem is that you are using a Label. A label is not a button and does not return a boolean value. Please refer to the docs for GUI.Label:
"Labels have no user interaction, do not catch mouse clicks and are always rendered in normal style. If you want to make a control that responds visually to user input, use a Box control."
If you want a button, you should try using GUI.Button which does return a boolean value.