Changing Azure User Access Administrator?
There are several terms:
- Azure AD tenant (something.onmicrosoft.com) that is directory of all users. In properties you can set that all users with "Global Admin" role have access to all Azure subscriptions.
- Azure subscription, has owner of user, this can be changed using portal.azure.com or via support ticket. It is typically user from organization (Azure AD tenant) in charge of the project / payments.
You can add additional users (free) in Azure AD tenant and provide access permissions to Azure subscription or resource groups (using IAM)