It seems from what I could find that TWC couldn't come to a mutual agreement with the NFL regarding the streaming of NFL games. read more
You can still watch NFL games though on the Xbox One with TWC using the WatchESPN app, along with of course just using the regular TV function of the Xbox One to watch it on your normal cable channels. read more
No, live streaming the network requires a cable subscription and in some cases even then you can't (I get NFL Network on my Time Warner cable but Time Warner isn't supported on the app for some reason). read more