To get the public IP of a computer or server on a Linux command line, you can use the following command for IPV4 addresses:
curl ipinfo.io/ip
You can obtain extended information about the IPV4 address (as JSON) via:
curl ipinfo.io
If you want to find out the public IPv6 address instead, you can use the following command:
curl v6.ipinfo.io/ip
For IPv6, you can also get the extended information via:
curl v6.ipinfo.io