I have a notepad++ file that is formatted with spacings etc... as well as a certain background/text colour I want to keep. How do I export that file to either an image or a pdf that will keep the spacings and the background/text colour?
Use print functionality to do that. To get background color go to Settings -> Preferences -> Printing and check WYSIWYG. Also you need to have pdf or image printer. Google for one of them for ex. "pdf printer windows 10".
Edit: To make whole page color as background first remove text from header and footer in Settings->Preferences->Printing it will remove header and footer from print. Second use pdf/image printer options to scale and set position for your document. If there is no options for printer (for ex. win 10 pdf printer ) you can reprint pdf again using pdf reader scaling on print setting. But for pdf if you not set page color as background color you will always see a little white borders.