Author of the blog/tutorial here. It looks like you don't have the pre-requsite installed. In the blog I call out the pre-req in pieces like this.
....In July, Docker released a beta for Docker Desktop that embedded these functionalities and, on September 15th, Docker released an updated experience in their Docker Desktop stable channel....
and then
...For now the only thing you need is Docker Desktop and an AWS account. For this test , I am using Docker Desktop (stable) version 2.5.0.1....
and finally
The core of this integration is built around a new tool dubbed Compose CLI (this is not to be confused with the original docker-compose CLI). This new CLI surfaces to the user as new functionalities in the docker command. While in Docker Desktop all this plumbing is completely hidden and available out of the box, if you are using a Linux machine you can set it up using either a script or a manual install. This new CLI is, essentially, a new version of the docker binary.
Eager to understand more how we could make it more clear / front and center that there were stuff to install and/or minimum software versions you had to use.
Thanks for trying it out!