Hassio Virtual Box Backups

I tried this suggestion, but it did not work. It goes back to the UEFI shell when I select “Continue”.
I repeated the process three times to be sure I was following the 12 steps properly, and I could not find the reason it did not work for me.

I also tried bobyard16 suggestion, but got stuck at the first command. When I type fs0:, I get a 'fs0' is not a valid mapping.

Any new ideas on this topic?