Hello, @Swabha!
Is the SHA-516 a hard requirement? This is the list of supported key types, algorithms, and operations for Azure Key Vault:
https://learn.microsoft.com/en-us/azure/key-vault/keys/about-keys-details
In PowerShell you'll be primarily leveraging Get-AzureKeyVaultSecret. This is a good write up from Virtual Geek that walks you through the process of using a Key Vault secret identifier url to get the secret value using PowerShell (script included at the bottom):