To access the Surface boot menu, shut down the device, then press and hold the volume down button while pressing and releasing the power button. Continue holding the volume down button until the Surface logo appears, and the boot menu will load. Alternatively, you can access the UEFI menu by holding the volume up button instead of the volume down button.
Accessing the boot menu
Shut down your Surface device completely.
Press and hold the volume down button.
While holding the volume down button, press and release the power button.
Continue to hold the volume down button until the Surface logo appears and the boot menu is displayed.
You can then use the touchscreen or a mouse to select a bootable device.
Accessing the UEFI menu
Shut down your Surface device completely.
Press and hold the volume up button.
While holding the volume up button, press and release the power button.
Continue to hold the volume up button until the Surface UEFI screen appears.
From the UEFI menu, you can change the boot order or adjust other settings. To boot from a USB drive, you may need to change the boot order to prioritize USB Storage.
Alternative method (from Windows)
If your Surface still boots into Windows, you can access the boot menu through Advanced startup.
Press and hold the left Shift key, then select Restart from the Start menu.
Once the "Choose an option" screen appears, select Use a device and choose your bootable device, such as USB Storage.

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