The Cloud CLI is typically used by human operators to interact with the Cloud API. Alternatively, it may be used for scripting or using the Cloud API with languages that are officially unsupported.
As an example, the following Bourne Shell script creates a resource group in the Microsoft Azure cloud and then creates a virtual machine belonging to that resource group:
#!/bin/sh
RESOURCE_GROUP=dominicanfair
VM_NAME=dominic
REGION=germanynorth
az group create --name $RESOURCE_GROUP --location $REGION
az vm create --resource-group $RESOURCE_GROUP --name $VM_NAME --image UbuntuLTS --ssh-key-values dominic_key.pub
When looking for documentation on how to manage cloud resources, you will encounter a lot of examples using the Cloud CLI. Even if you wouldn't normally use the CLI, instead preferring a solution such as Terraform, having the Cloud CLI at hand may help you with debugging infrastructure problems.