DNS in virtual box Ubuntu 20.04

sudo systemctl enable systemd-resolved.service

sudo vim /etc/netplan/00-installer-config.yaml

Add Google DNS:

network:
  ethernets:
    enp0s3:
      dhcp4: true
      nameservers:
        addresses: [8.8.8.8, 8.8.4.4]
  version: 2

sudo netplan apply