can't log in to the modem router -

[crowella]

 I purchased what i beleive is the C6300 off facebook marketplace, it came in a box which is for Nighthawk c1150v.  the device that came has no product label at all.  I currently have xfinity rented modem router and its connected.  I have my laptop w ethernet connected to the c6300,  ive done a reset on the modem/router, when i try to log in it says its not connected to the wifi.

what am i doing wrong?

in order to use it for xfinity i need to activate it and i need the CM MAC number.  i can get the MAC off computer configuration but xfinity says they need the cm mac.

HELP!?!?!?!?!

[plemans]

try logging in via 192.168.100.1

Then go to advanced tab and looks the advanced home page. one of the icon's lists ip info/mac info

[crowella]

It says it can’t reach the page like it’s not connected

[plemans]

might be a reason it was sold on facebook marketplace