1. Check if Docker is installed. Run the following command: 
    docker info
    Sample output: 
    Client:
 Context: default
 Debug mode: false
 Servers:
  default:
    Host: localhost
    Engine:
      Version: 20.10.14
      API version: 1.44
      Go version: go1.17.15
      Git commit: 8668127
      Built: Thu Apr 1 06:02:55 2021
      OS/Arch: linux/amd64
      Experimental: false
    Kernel: 5.15.0-52-generic
    Operating System: Ubuntu 22.04.1 LTS
    Total Memory: 31.8GiB
    CPUs: 8
    If you see this output, Docker is installed, but the user may not be added to the Docker group.
  2. Check if the user is in the Docker group. Run the following command: 
    grep -i docker /etc/group
    Sample output: 
    docker:x:999:root,$USER1,$USER2,etc
    Verify if your username is listed. If not, add the user to the Docker group:
  3. Add user to the Docker group: 
    sudo usermod -aG docker $USER
    Example: 
    sudo usermod -aG docker Michael
  4. Verify the user is added. Re-run the group check: 
    grep -i docker /etc/group
    The output should now include your username, e.g.: 
    docker:x:999:root,michael
  5. Reboot the server: 
    sudo reboot
  6. Once logged back in, restart Docker: 
    sudo systemctl restart docker
  7. If no output is shown when running docker info, suggest downloading and installing Docker properly.