You almost certainly have a virus. Sounds like your only option is to use the
Windows Media Creation Tool to reinstall the OS from that. First, plug a 16GB USB stick into a non-infected computer, reformat it.
To reformat, right click the Windows button in the bottom-left corner, and select "Disk Management". Now, at the bottom, right click the box with the letter corresponding to your USB stick (To find out what it is, just look through File Explorer for it) and select "Format". Under "Volume Label" choose "NTFS". Let the "Allocation Unit Size" stay at its default, and don't click "Perform a Quick Format or Enable File and Folder Compression".
Now, download the previously mentioned Windows Media Creation Tool onto the flash drive and go through the setup.
With your infected computer off, plug the flash drive in, and unplug your regular drive that has Windows installed. Now, once you're booted into the setup, plug your regular hard drive back in and begin. If you want more details on the making of the Media Creation Tool and installing Windows on your computer, these two videos explain it simply and clearly.
Installing Media Creation Tool Onto USB Drive
Installing Windows Onto Your Computer
Now, keep in mind you will
lose your files, but this is your only option for recovery. If you want to risk plugging the infected drive into another PC and copying the files onto it, you can, but it's not safe by any stretch of the imagination.
Anyway, I hope this solves your problem!