Hello @Nitin S , thank you for reaching out. To list all the users and groups that are already added to a specific application registered in Azure AD, you need to use the following Microsoft Graph API: https://graph.microsoft.com/beta/servicePrincipals/{id}/appRoleAssignedTo
To use this API, make sure you have the following permissions added in your app registration using which you would make the Graph API call.
More details about this API can be found here: https://learn.microsoft.com/en-us/graph/api/serviceprincipal-list-approleassignedto?view=graph-rest-1.0&tabs=http
Hope this helps.
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