Tried installing Windows 10 on MacBook Pro from a USB...failed I attempted to install Windows 10 Home on my son's MacBook per the instructions and assurances of others as to how simple this would be. I apologize but apparently I am a moron because not only did it not install whatsoever but now I have a single line on the screen saying "no bootable device--insert boot disk and press any key". I have no idea how to simply get back to a functioning status. Any suggestions?
Try to install Windows 10 via an empty DVD by burning the ISO to it through disk utility. I used a DVD-R with 4.7GB of space on it and after the Mac restarts when BCA finishes it should boot into the Windows installer. 

If the problem persists just restart the Mac again and hold Option as soon as it starts and you should see a boot menu it should show either EFI boot or Windows whether your Mac supports EFI boot.