@IChris
Pressing F10 brings up the BIOS/UEFI options -- which is not what you use to load Windows.
You need to press F9 repeatedly to get the Boot Devices menu. If the USB drive does not show up there, you are stuck because then, you WOULD have to get into the UEFI options to disable Secure Boot, as with that enabled, no USB drives are going to show up in the Boot Devices menu.
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