To actually boot the drive, reboot your Mac and hold down the Option key while it boots. You’ll see the boot options menu appear. Select the connected USB drive. The Mac will boot the Linux system from the connected USB drive.

Can you boot Linux on a Mac?

If you just want to try Linux on your Mac, you can boot from a live CD or USB drive. Insert the live Linux media, restart your Mac, press and hold the Option key, and select the Linux media on the Startup Manager screen.

How do I force my MacBook Pro to boot?

Press and hold down the Command (⌘) and Control (Ctrl) keys along with the power button (or the ‌Touch ID‌ / Eject button, depending on the Mac model) until the screen goes blank and the machine restarts.