Question: how to get azure subscription using powershell?
Answer: Get a list of all subscriptions in your account. Azure PowerShell Copy. Try It. Get-AzureRmSubscription. ... 
Set the default. Azure PowerShell Copy. Try It. Select-AzureRmSubscription -Subscription "My Demos"
Verify the change by running the Get-AzureRmContext cmdlet. Azure PowerShell Copy. Try It.