How to Install Docker CE on Ubuntu 18.10 Cosmic Step By Step

Docker CE Ubuntu 18.10 - Installing Packages

2. Login as SuperUser
   The default Docker Administration Requires this Privileges..

   sudo su

   Then to Achieve this Session:

   exit

3. Check if a Previous Docker Version is Installed
   With:

   which docker

   If Yes then Remove that with:

   apt remove docker docker-engine

4. Install PreRequisite Packages.

   /napt install apt-transport-https 
   ca-certificates software-properties-common