I am trying to set up a wired modem as an additional internet for my personal computer in a group home which already has wireless internet via a router. I would like this because the internet wireless is unreliable when I play games sometimes. I have a modem and it's hooked up to the cable port in the wall and to my computer, but when I try to use it Xfinity prompts me to get a code from them for it to work that requires either the mobile phone number of the account (Which does not belong to me, it belongs to the group home) or the name and password of the account. The group home manager will not give me the number or the name/password. Is there any way I can get the wired modem working? Thanks.
You would have to set up your own account with Comcast, and even then some markets will not let you set up a second account in a household which already has service.
If WiFi is unreliable, your only other choice is to either string a long Ethernet cable from the existing gateway to your device, or a different connection approach like Powerline or MoCA adapters.