I'd get ready for an OS install. I can only guess this is a Windows OS but can't tell which. Most had a System Restore to go back to where it worked.
Next time you know to not delete those files.
One day I was just deleting unused files. I dont know if I deleted something importan.The next day internet were limited. I can provide this info:
-it says 'limited' under connected wi fi.
-troubleshoot problems results (There might be a problem with the driver for the wi fi adapter (ethernet adapter too)) It can't fix it automaticaly.
-when I enter ipconfig in cmd it just says Win IP config and that is it, no information at all...
-cant connect to my router by typing default gateway in browser.