This video is for older versions of Windows or Mac OS that are not supported by Docker for Windows or Docker for Mac. It is generally recommended that you upgrade your operating system to a supported version. If that is not an option for you, you can use the legacy Docker Toolbox.
Go to docs.docker.com, select "Get Docker", then "Docker Toolbox". In this part of the manual you can find the installation instructions for the Toolbox on Mac and Windows. Follow the instructions, then watch the “Docker Machine” video next.