Hello @Sandeep Chinni , you can use the same app registration for both front-end and web api applications. You will issue an ID token to authenticate against the former and an access token to get authorized by the latter. For this you need your app registration to expose a web API. Aud claim remains the same for both tokens. SSO applies only between clients like your front-end app, once logged in your frontend app you will acquired an access token for your API.
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