I have Comcast and they basically force you to get a "land line" through them (although I guess it's closer to VOIP?) for a cheaper package. Mine isn't plugged

I have Comcast and they basically force you to get a "land line" through them (although I guess it's closer to VOIP?) for a cheaper package. Mine isn't plugged into a phone though, I don't even know what the phone number is.