How to get my brand new Xfinity voice landline working on my house phones?

We just had a brand new Xfinity internet service w/ landline voice installed on Friday last week. The internet is working great.  However, I was extremely dissatisfied with the technician for claiming that he "cannot help us in connecting our landline up".  I was annoyed.   The technician admitted he didn't even see the landline on the order (at first) and only noticed it after I asked about it when he was almost done installing the main cable into our house for the internet. He then said that he needs to have access to an existing phone jack. I told him the nearest one is in the other room, and would need at least 50 feet of phone cord to reach it.  He said they "only carry 10-foot lengths of phone cord".  Annoyance building.  Nobody informed me when I made the order that the homeowner would be responsible for providing materials in order to get part of our order installed.  I asked the technician to get me in touch with his supervisor, and he said he doesn't have a supervisor.  Annoyance bordering on anger at this point.  The tech was unable to provide me with a single solution ... so he called his supervisor (the same supervisor he claimed earlier he didn't have!).  Now I'm angry, but I was able to hold it inside and not explode on the tech.  According to the tech, his supervisor said the only other option was to tear out what they already installed and relocating it to the far side of the house in order to get closer to an existing phone jack.  Uh...no!  That's ridiculous when all you need is a longer phone cord. I told the technician to just finish the installation of the internet.  I'll handle the phone landline issue. 

So... I am asking how do I get my landline voice service in my house?  Do I just need a phone cord from the gateway to the nearest phone jack in my house?  Or is it more in depth than that?  I have no issue going out to buy a 50-foot-plus long phone cord and run it to the nearest phone jack.  

Thank you.