Basic Nmap commands
#ifconfig
IP= 192.168.100.04
The highlighted IP from the output indicates that our system is using 192.168.100.0 subnet mask and the range is 255. Thus our network IP range is from 192.168.100.0 to 192.168.100.255.
$ nmap -sP 192.168.100.0/24
ref:https://vitux.com/find-devices-connected-to-your-network-with-nmap/