Chuck Davis was very recently
heard to utter:
I know they are four-letter words, but "read" and "help"
should become your mainstays. Choose Help and search for
"default font" The answer that you are looking for is the
first listed and just waiting for you to read it.

Note that you have to have Publisher and your firewall application
configured to allow Publisher access to the internet to get updated help
content in order to be able to read this help article.

--
Ed Bennett - MVP Microsoft Publisher