To do Alt + P B I on Mac in Excel, download and install Accelerator Keys, then press Option, followed by P, B, and I.
Command: Insert Page Break
This is how to do Alt + P B I 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 + P B I inserts a page break at the current cell position. A horizontal break is inserted above the active cell, and a vertical break is inserted to the left, controlling where the page splits when printing.