How Azure Webapp can retrieve secrets from an Azure Keyvault ?

1. Go to your Webapp
2. Select the option Identity
3. There are two kinds of Identity :  1) System assign and  2) User assign

4. Click on System assign option and enable/ON it. (system assigned managed identity).
( once it is registered, can be granted permissions to access resources protected by Azure AD).

5. Now the Azure Webapps can able to retrieve secrets from the Azure Keyvaults.