Uninstall old versions

$ sudo apt-get remove docker docker-engine docker.io

add repo

sudo add-apt-repository\"deb [arch=amd64] https://download.docker.com/linux/ubuntu \ $(lsb_release-cs) \ stable"

update

sudo apt-get update

install

sudo apt-get install docker-ce

links

links:ubuntu install docker

how-to-install-and-use-docker-on-ubuntu-16-04