In order to delete all Azure storage accounts that start with mystorage, for example, you’ll first need to run a Bash shell instead of PowerShell. Then, type:

az storage account list --query "[?starts_with(name,'mystorage')].[name]" --output tsv | xargs -L1 bash -c 'az storage account delete --name $0 --yes'

In order to delete a storage account in Azure, type:

az storage account delete --resource-group --name yourstoragename