Linux Shout published a tutorial about installing ifconfig in Ubuntu 20.04/18.04 or older versions.

How to install ifconfig in Ubuntu 20.04/18.04 or older versions

Check the Ubuntu System IP address by installing ifconfig on it via net-tools, however we can use ip addr as well that doesn't need ifconfig

How to install ifconfig in Ubuntu 20.04/18.04 or older versions - Linux Shout