On Windows 10 a black screen is among the most difficult problems you can face with your computer because it won't give an error code or message you can use to determine the root of the cause to fix it.
Although a black screen could appear due to many things, it's usually related to graphics drivers or compatibility problems with a new version of Windows 10. It could also happen when the device receives a buggy system update. Or it could end up being a hardware-related problem with the display, video adapter, or physical connection.
Whatever the reason might be, Windows 10 offers many ways to determine the cause and solve this problem, whether you have access to the desktop or the system won't even start correctly.
Sometimes, a black screen happens because Windows 10 will lose its connection with the display. Using the Windows key + Ctrl + Shift + B keyboard shortcut can restart the video driver and refresh the connection with the monitor.
When you perform the wake action, you will hear a beep and activity on the screen indicating that Windows 10 can respond to the command, and it is trying to establish a new connection.
Alternatively, assuming that Windows 10 is responsive, you can use the Windows key + P keyboard shortcut to open the "Project" fly-out menu. Then hit the P key again, and hit the Enter key to switch between the different display modes to see if the black screen disappears. (You will need to repeat the steps four times to allow cycling through all the possible modes.)
If the screen is still showing in black, press and hold the power button for about 10 seconds to shut down the device. Then press the power button again to restart.