Here are the commands I talk about in my How To Configure A Static IP Address On Ubuntu Server video.
01-netcfg.yaml
network: version: 2 renderer: networkd ethernets: ens18: dhcp4: no addresses: - 192.168.1.100/24 gateway4: 192.168.1.1 nameservers: addresses: [192.168.1.1, 1.1.1.1]
99-disable-network-config.cfg
network: {config: disabled}