Erasing the Hard Drive on a MacBook Pro
I have upgraded to a MacBook Air and want to give my MacBook Pro to our local School so I've been attempting to erase the data on it first. It's a Intel MacBook Pro mid 2014 running Big Sur. I've followed the guide on the apple support site and using Disk Utility have managed to erase the Mackintosh HD Data and am now left with just the Mackintosh HD, which seems empty (see pic below) and under Disk Image - macOS Base system (see pic below). Do I need to do anything else, like reinstall Big Sur when I leave Disk Utility? What is the macOS Base system and what is its purpose? It would be useful if this was mentioned in the support pages.
MacBook Pro