@Nelito Germano Vieira Junior ,
To allow users in other Entra/Azure tenants to sign into your web app, you need to add the users as guests in your tenant. You can invite the external users to access your app using their own Entra credentials. You can invite the guest users following this process: https://learn.microsoft.com/en-us/entra/external-id/b2b-quickstart-add-guest-users-portal
Let me know if you run into any issues.
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