TC8717T with WIFI turned off - Time Warner Internet

This question is about "TC8717T with WIFI turned off", with Time Warner Cable internet and apps. I am not paying TWC/Spectrum $5 for WIFI! After having them turn the WIFI off, as I have a UAP-AC-PRO. Know the router is at and dhcp is not 100%. How do I manage the firewall & port forwarding? Support is completely useless as they doesn't understand TCP/IP or subnets! I was told to return the modem to a store because no one at TWC understands their own system! See -

What IP address does my connected router have to be on to get all the traffic - port 23, 80, 443, ....? Or is my only option to buy a 2nd cable modem because of the idiots at TWC/Spectrum are incompetent? Is TWC/Spectrum advertising completely false/fraudulent & you are NOT paying $5 for WIFI but a working cable modem, even though I have to keep their modem connected for the phone line? If this is TRUE, my next call is to NYS Attorney Generals office for false advertisements, they are already trying to kick Spectrum out of NYS. At lease FIOS has a brain and gives you an Ethernet port that works.

TC8717T with WIFI turned off?