To consume an API you need to provide a JWT token with the required permissions to send along with the call. This token can be generated by calling the Microsoft token provider that takes the clients id, secret and the scope for which the token should provide access. The token returns a role on the backend service that is validated. This role must be set on the managed identity or application registration in Microsoft Entra ID of your client. This must be done before retrieving the token.

In addition to this JWT token you need to provide a subscription key within the API call. This key can be requested in this portal, and is on a product level.

For further details on the onboarding process visit: Self-service - API - Onboarding