In this example we are going to create a service called "App Configuration"
1) In the azure portal we look for the resource "App Configuration"
2) We fill the creation form
3) We go to the option "Configuration Explorer"
4) in the create option we are going to insert 2 secrets
5) We fill in the name of the "key" and the value that it will contain
6) Here we see the 2 keys that we have created
7) we are going to create a resource "Key Vault"
8) We fill out the form and click on the create button
9) We go to the "Secrets" option and insert a secret
10) we put a name and the value
11) at the end the saved secret is shown
12) Now we are going to insert a "Key Vault reference"
13) we fill the form as follows with the previously saved secrets
14) we will notice that the row will have a key vault icon, in this way azure app configuration is complemented with azure key vault
15) we see that the secret that is in keyvault is not shown but rather the url of the secret
16) We create a project in .net following the tutorial on this page
17) in the code we will show the value of the key "secret1" resulting in the following