Create Managed Apple IDs in Apple Business Manager
Managed Apple IDs, roles, and passwords
When you create each account, you assign a role that defines the privileges for that account.
Create new Managed Apple IDs with verified domain names
In Apple Business Manager , sign in with an account that has the role of Administrator or People Manager.
Click Accounts in the sidebar, search for an account in the Search Accounts field, then select the users from the user list. See Search for user accounts.
Click Edit in the Account row, then click the Add button to select what the Managed Apple ID will start with.
You can also enter text, such as a period, in the field.
Select a domain from the list, then click Continue.
Click Close, or wait until the activity has finished, then click Done.