Create a portable company file quickbooks mac 2019

I can not update QB on my mac to the newest version because I am still running Catalina OS.  I can't upgrade to the latest Mac OS until I upgrade my QB.  It's a catch 22.  Therefor, I am trying to create a portable company file so that I can upgrade my QB and have a copy incase something happens and I can not get into QB, I can import a complete file so I do not loose anything.

I am unable to find instructions for Mac 2019 QB desktop version.  Everything is for PC and or newer versions.  When I call in, the people in India are of no help.