In some cases due to external devices plugged into the PC/laptop might cause the black screen issue after updating to Windows 10
• First, unplug all the external devices.
• Then restart the PC/laptop.
• And if you notice after unplugging, black screen disappeared, then plug the device again to see which piece of hardware is causing the problem.
• To fix the problem install the updated drivers for the hardware.
Hope doing this fixes the black screen issue in Windows 10 or else visit the Microsoft Official site for the solutions