Hi Philippe Bouëssel du Bourg,
Thank you for reaching out to us on the Microsoft Q&A forum.
Please note that for this exercise, you must have an Azure subscription. You can explore the available Azure subscription options here: Azure Subscription Options.
It seems that you may not have the necessary permissions in your current Microsoft Entra environment to create users in the Identity service. To resolve this, I recommend creating a new Microsoft Entra tenant. This will ensure that you have the appropriate permissions, such as User Administrator, which are required to perform user creation tasks.
For more information on roles and permissions, you can refer to the documentation here: Microsoft Entra Role-Based Access Control.
If you continue to experience any issues, feel free to share your concerns in the comments. We are here to assist you.
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