To do Alt + N P O B on Mac in Excel, download and install Accelerator Keys, then press Option, followed by N, P, O, and B.
Command: Photo Browser (Place over Cells)
This is how to do Alt + N P O B on Mac in Excel with Accelerator Keys, the native ribbon and alt key shortcut solution for Mac users who get more done with Excel.
Alt + N P O B opens the Mac Photo Browser to select an image to place over cells as a floating picture. The image will be positioned above the worksheet and can be freely moved and resized.