Can anyone help me create a template for MS Word 2010 from a .PNG file.

Today I found a site that offered free Christmas templates for MS Word and when I saved the file it was saved as a .PNG file. I opened word and the only way I could see how to use the file was to bring it in as a photo and position it so it covered the whole page. That being said, I could not see how to do anything else with it as I could not type text on top of the graphic image. Can anyone explain to me how to go about making this so I can type a multiple page document so that each time I start typing a new page the background image appears and you can type inside the frame of the imported picture. Thanks in advance for any help.