Remove background isn't removing the background
I've followed the instructions to remove a background (white background of a headshot - should be easy) but all I get is a mask and no transparent background (the goal).
In searching for possible answers, I've found instructions to go to Properties > Artboard and set it to transparent but I don't see Artboard anywhere in the properties panel. Or anywhere else for that matter (where I can set "transparent").
What am I missing please?
Thanks for any help.

