Connecting Internet gateway when my cable outlet is being used by TV box
I have TV service through Xfinity using a Pace model RNG 110 TV box. I am attempting to add internet with the Xfinity provided gateway Model XB6-T. The TV box is currently using the cable outlet. If I connect the internet gateway to the cable outlet, how do I connect the TV box to the gateway? Is a splitter required? Use the ethernet cable in the self-install kit?