I still use docker.io which is now considered an old version, so you probably want to use the recommended Docker CE (Community Edition) instead. More info here:https://docs.docker.com/install/linux/docker-ce/ubuntu/#install-using-the-repository
At this point, most docker commands including docker ps
require sudo
permission, and this should be avoided. Next section addresses this.
Run these commands. Some are straight from Docker's docs: https://docs.docker.com/install/linux/linux-postinstall/