You don’t need to install Docker Engine alongside Docker Desktop unless you really need it. Docker’s documentation clearly states:
Docker Desktop for Linux and Docker Engine can be installed side-by-side on the same machine.
Using a dedicated storage location for Docker Desktop prevents it from interfering with a Docker Engine installation on the same machine.
While it’s possible to run both Docker Desktop and Docker Engine simultaneously, there may be situations where running both at the same time can cause issues.
The issue you are facing is due to the missing Docker repository on your system, which you can resolve by following a part of Docker Engine’s documentation as follows:
sudo apt install -y ca-certificates curl gnupg lsb-release
sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
sudo apt update -y
After that, you can go on with the installation of Docker Desktop:
sudo apt install ./docker-desktop-<version>-<arch>.deb
P.S. Don’t get panic if you see the error below at the end of the installation process. Just ignore it and you’ll be fine 😉
Download is performed unsandboxed as root as file docker-desktop-
<version>-<arch>.deb couldn't be accessed by user '_apt'. -
pkgAcquire::Run (13: Permission denied)