Hello,
You can add images as the background of the main header and header bottom from WoodMart >> Header Builder >> Edit Header.
Screenshot for Clarification: https://ibb.co/4s4JFnR
You cannot display one image as the background of both rows of the header; you need to add them separately.
If you are trying to ask anything else then provide some relevant screenshot of the specific area to check it myself and help you out accordingly.
Best Regards.