Push and hold the power button for a few seconds. It should force a shut down. Does with mine anyway.
Most computer will force a shutdown holding down the power button.
But Sed , I know because it's a known issue to ME .. With Windows 10 a Black Screen at Boot Up.
open task manager and sign out and then back in ....( Cntrl-Alt-Delete)
you might even have to do it a few times till it boots to your desktop .
It's happened to me and still does sometimes.
If you go on youtube you'll see a few reasons why and what a few different people say is the fix.
It appears to be a windows 10 glitch maybe from some a one update maybe, not forsure.
I think Windows has it built into the OS boots for various devices so when windows boots it
thinks it's booting to another device , but sign out and back in will get you to the desktop.
That's what I know ....
........ So I'm trying to see if we are having the same problem black screen at boot up
but mouse and keyboard works , is that your problem ?