Can I change the default font of headers and footers?

[Stonsey]

Do you know if it's possible to do the above and if so how?

 

[Jezebel]

Same way as for any other part of your template. Define the style, set the
font.

 

[Stefan Blom]

Modify the font of the "Header" and "Footer" paragraph styles. For
more, see http://www.shaunakelly.com/word/styles/ModifyAStyle.html