Both IPv4 and IPv6 addresses can be configured in the configuration mode.

LYSH@MyHostName# configure
configure# ip add -h
usage: ip add [-h] interface ip [gateway]

positional arguments:
  interface   Ethernet interface name
  ip          IPv4/Subnet Mask or IPv6 address/prefix
  [gateway]   IPv4 or IPv6 address

optional arguments:
  -h, --help  show this help message and exit

Configuring new IP addresses

LYSH@MyHostName# configure				// Enters configuration mode.
configure# ip add eth0 192.168.0.3/24 192.168.0.1	// Configures an IPv4 address, subnet, and gateway.(i.e. 192.168.0.1)
configure# ip add eth0 2000:4::40/64 2000:4::1		// Configures an IPv6 address, prefix, and gateway.(i.e, 2000:4::1)
configure# netplan apply				// immediately apply the configurations.
configure# exit
configure# show interface
LYSH@MyHostName# ping 192.168.0.1		
LYSH@MyHostName# ping6 2000:4::1				

Deleting an IP addresses

LYSH@MyHostName# configure				// Enters configuration mode.
configure# ip delete eth0 192.168.0.3/24		// Deletes an IPv4 address(i.e. 192.168.0.3/24)
configure# ip delete eth0 2000:4::40/64			// Deletes an IPv6 address(i.e. 2000:4::40/64)
configure# netplan apply				// immediately apply the configurations.
configure# exit
configure# show interface