If you don't want to reinstall Windows, I recommend you visit the malware removal section.
Malware Removal Assistance For Windows
If you're certain that you want to reset your OS, you have some options.
Do you need to back your files up? If you do, don't reset your PC just yet.
1. This option sometimes fails, so you may want to follow option 2 as a backup plan. Power on your PC. Click the Start button. Click the Power button. While holding Shift, press Restart. Once the PC restarts, choose Reset this PC. Again, this fails sometimes if your recovery partition is corrupted.
2. Make your Windows 10 installation media follow this link:
Download Windows 10
And then you can boot from the USB and reinstall Windows normally. You will probably need some help with wiping your drive and re-partitioning it. Post back here on another device for further instructions.