Many, or most, computers now come with boot options disabled. You have to work hard to get a PC to boot up from anything other than the hard drive. Well, that is what it sounds like to me after reading this item from a MS forum.
Disabling Secure Boot You may need to disable Secure Boot to run some PC graphics cards, hardware, or operating systems such as Linux or previous version of Windows.
Secure Boot helps to make sure that your PC boots using only firmware that is trusted by the manufacturer. You can disable Secure Boot through the PC’s firmware (BIOS) menus, but the way you disable it varies by PC manufacturer. If you are having trouble disabling Secure Boot after following the steps below, contact your manufacturer for help.
That might indicate why the OP is having trouble with USB boot.
Or maybe not.
