Remote Desktop for a teacher without unix experience - proxy help

I am a teacher in a school with a three hour period. There are students who are addicted to wasting time and I used to use a proxy that doesn't exist to shut off the WAN but is still able to access our mac mini server for file sharing. It worked at one point but not in Sonoma. I really am lost on this but here is a command I used to use.

networksetup -setwebproxy "Ethernet" 10.1.1.13 80 on

networksetup -setsecurewebproxy "Wi-Fi" 10.1.1.13 80 on

networksetup -setwebproxy "Ethernet" 10.1.1.13 80 on

networksetup -setsecurewebproxy "Wi-Fi" 10.1.1.13 80 on

Any help would be appreciated. Thank you