Basic Installation

Refer: https://linuxconfig.org/how-to-install-docker-on-ubuntu-20-04-lts-focal-fossa

Use the apt command to install the docker.io package:

$ sudo apt install docker.io

Start docker and enable it to start after the system reboot:

$ sudo systemctl enable --now docker

Optionally give any user administrative privileges to docker:

$ sudo usermod -aG docker SOMEUSERNAME

Reboot Computer to Verify

$ reboot

Stop Docker from auto starting upon reboot

Refer: https://askubuntu.com/questions/766318/disable-docker-autostart-at-boot

sudo systemctl disable docker.service
sudo systemctl disable docker.socket

Then start and stop Docker as a service

sudo service docker start
sudo service docker stop

Check docker version:

$ docker --version

Verify Installation

$ docker run hello-world

Post Installation Items

Refer: https://docs.docker.com/engine/install/linux-postinstall/