From the sounds of it, it appears your PC is finding an issue during startup and is unable to repair it so just sits there doing nothing.
There's some steps here, if you could follow them carefully, it may help you with your issue (this guide is for Windows 10, if you are running another version of Windows, let me know and don't follow these steps):
There's a Tom's Hardware video here: (http
/www.tomshardware.co.uk/faq/id-2569556/safe-mode-windows.html) that shows how to access safe mode when your PC won't boot (it's the second demonstration in the video).
If you follow this and manage to get into safe mode then if you would please follow these steps:
1. Press "Windows + R" at the same time
2. Enter "control wuaucpl.cpl" (without speech marks) followed by enter
3. Windows Update should open
4. Select "Scan for Updates"
5. Install all updates including optional ones
6. Reboot and attempt to boot to the standard desktop
7. If this fails, follow the video again to get back into safe mode. If however, it works, then follow the first part of the video to get into safe mode.
8. Press "Windows + X" at the same time
9. Select “Command Prompt (Admin)”
10. Accept any User Account Control popup for “Windows Command Processor”
11. Enter "sfc /scannow" (without the speech marks) into Command Prompt followed by enter
12. Let the scan complete fully