I already knew it.
In that case you need this Solution: https://support.microsoft.com/en-us/help/17085/windows-8-restore-refresh-reset-pc
Scroll down and Click > Refresh your PC without affecting your files and follow on easy method.
Relax, doing this may not affect your personal files from any other partition, your drivers, may kept. and your OS will go back to a day when you’ve fresh installed it. Completely fresh. It’s like your Current OS will get reinstall over again without using formatting. Good luck!
WARNING: Your System data dealing with viruses, so Do not open any other partition beside C partition until unless you scan over all drives. But if virus only contains in C drive then it might definitely gone by resetting but who knows where actually it’s located so below method will fix it permanently.
NOTE: If you’re dealing with Virus, and not sure where actually virus rest, so kindly do not touch any other partition unless you install and scan System after resetting OS. Kindly download Malwarebytes and scan System. if anything caught kill it and restart system. After that use another anti-virus for double check. something like Hitman pro. scan and kill infection. restart system. That’s all. you’re good to go.
Kindly follow this Video to scan and kill viruses: