Hello @Xiang Li
If you have a paid subscription to Microsoft 365, you also have a free Azure AD subscription. You can use Azure AD to create and manage user and group accounts. To activate this subscription, you have to complete a one-time registration. Afterward, you can access Azure AD from your Microsoft 365 admin center.
to register your free Azure AD subscription, see use your free Azure AD subscription. Don't go directly to azure.microsoft.com to sign up or you'll end up with a trial or paid subscription to Microsoft Azure that is separate from your free Azure AD subscription with Microsoft 365.
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