In need of cable line replacement/installation!!

> Subscribed a few weeks ago for xfinity internet and was going to do a self-install.

> Coax cable arrived, and we bought a compatible modem.

> Plugged everything in, but the "Online" globe symbol on the modem does not light up.

I've now realized that my household has never had or used cable, and so our coax outlet's wiring doesn't actually work. Either the underground cable needs replacement, or xfinity has to install their own cable line to transmit service. I'm not exactly sure, but would like a technician's opinion.

I've been scouring forums and xfinity's website for over an hour, searching for a way to get a technician appointment. Can someone help me?