I want to be able to boot from a USB thumb drive to re-install the Elementary OS. I've installed Elementary OS on my old MacBook Air, and it's only a single boot, no dual-boot or Mac OS anymore. So my question is how can I change the boot order?
WHAT I'VE TRIED: 1) When I hold the "Option" key down I get a list of wifi connections to choose from, instead of being able to choose between booting from the USB or the Hard drive.
2) Holding down the "OPT CMD 0 F" doesn't work to open up the EFI to make boot order changes.
Any help would be greatly appreciated. Thanks!