original mac address:
ifconfig eth0
Turn off your network interface:
ifconfig eth0 down
Use macchanger to randomly generate new MAC address and assign it to eth0 network interface:
macchanger -r eth0
ifconfig eth0 up
If for example a specific MAC address is required use macchanger as follows:
macchanger -m b2:aa:0e:56:ed:f7 eth0
References :
https://linuxconfig.org/change-mac-address-with-macchanger-linux-command