It's not really clear from your post what "not loading" means, nor what you mean with "go to default settings".
The worst case, is that you need to find a Windows 8 or Windows 8.1 disk - or preferably a recovery disk for your specific device - to do a clean install of Windows.
But it might help to download and burn an anti-virus disk on another PC and boot from that to see if it might repair your system.
When all is working again, better research the idea of buying an external hard disk and making an image copy of a working system, so you can go back to that. It's built into Windows, and there are free third-party programs also that do the trick.
Kees
I believe I have a virus but it's become so bad to where I can't download any antivirus and can't go to default settings because it says the necessary files to do so is not there and I don't know what to do.

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