How to enable and work talk daemon in terminal?

Ive been recently been playing around with terminal and discovered the "talk" command. After some internet research I think I've done everything Ive need to do. So far I've done:

- enabled talk daemon with "launchctl load -w /System/Library/LaunchDaemons/ntalk.plist" command as a root user

- checked is "mesg" command is set to "Y"

- done this on both computers

Im trying to connect to my friend in a different city, I know his IP and he has done the same process on his end but the connection can't seem to be made. Im thinking I need to port forward...

Any ideas? Thanks

P.S. I know this is old unsupported program these days but still need help.