@Шитиков Олег
Thank you for your post!
As mentioned by SMil, you can find all of our REST APIs via our Azure REST API reference documentation. When it comes to creating new Azure Active Directory tenants, this can only be completed through the Azure Portal - Create a new tenant in Azure Active Directory.
Tools for Managing Azure AD:
Azure AD identity and access management API overview
Azure Active Directory PowerShell for Graph
AzureAD PowerShell Module
Managed Identity REST API reference
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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