Sounds like your Windows install is corrupt. You can try running one or more of the following commands to attempt a repair from an elevated command prompt
- chkdsk /f /r t then press Y to run it at the next reboot and reboot
- DISM /Online /Cleanup-Image /RestoreHealth
If neither of those resolves the issue you can do a re-install over the existing install, you will just need to download the ISO and create a bootable media
If that doesn't work, then you are looking at a clean install which will wipe out everything, so if you have data be sure to back it up.