Manual proxy settings getting turned ON again and again

Without looking at videos, I suggest going to c:\windows\system32 and right click on the file cmd.exe. Select RunAs Administrator and it the Enter key.

At the C:\ prompt type
net user Administrator /active:yes
then hit Enter. Close the form and restart the machine then log in as Administrator. Untick the Proxy box in Internet Options>Connections tab>LAN button and click Apply and OK.

If it reverts by itself, download the free version of MalwareBytes from www.malwarebytes.org and scan with that to see what's doing it.