Hello @Amandeep Patro , to get the service principal for your Salesforce application you need to call the MS Graph List servicePrincipals operation like this:
/servicePrincipals?$filter=appDisplayName eq '<salesforce app display name>'
Or
/servicePrincipals?$filter=appId eq '<salesforce app (not object) id>'
Also to get users assigned to the application you need to call List appRoleAssignments granted to a service principal.
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