VMware Tanzu does not publicly distribute or provide a way for customers to download the Maestro CLI. The Maestro CLI is closed source and part of the private OpsMan source code. It is not part of the open source Cloud Foundry.
However, the binary is located on the OpsMan VM in the /usr/local/bin/maestro directory. Customers can copy the binary from there and place it wherever they'd like.
Maestro can be run from anywhere if you're logged in to your BOSH and Credhub using the appropriate environment variables. More information on setting the environment variables are located here.
If customers want to use the Maestro CLI without OpsManager, they can SSH onto the OpsMan VM, copy the binary from the VM, and place it anywhere they'd like.
scp ubuntu@<opsman-fqdn-or-IP-address>:/usr/local/bin/maestro .
Copy the binary to /usr/local/bin and make it executable.
sudo cp maestro /usr/local/bin
sudo chmod a+x /usr/local/bin/maestro