Your question seems a little bit underspecified. So not sure if I can really help you. The host is your public IP address so if you are logged on the machine on which the lightning node runs you can try typing curl -4 https://icanhazip.com/ to the command line.
if you are running c-lightning you can do: lightning-cli getinfo and it will also depict your public IP address. Not sure if the other implementations have an API call to depict this information.












