What most naturally follows?

How to make free phone calls and listen on a tv
Download a voip (voice over ip) program on your computer.
In order to place calls through your tv, you will have to use a computer to do the calling. One of the most popular programs for this is skype, though there are also others available.
Skype is one of the best choices because you can setup a phone number that anyone can call you at. See this guide to get skype installed and configured on your computer.