iPad Pro mail group

You will need to create a Contact List (i.e., a Group), within your Contacts App, for the intended recipients.

Each member of the list must have a contact card within your Contacts App - obviously with the recipient email address.

To create your list, ensure the Contacts Sidebar is visible; tap the Sidebar button at top-left of the Contacts Window to expose the sidebar.

To create a new list, tap the Edit button at the top of the sidebar - then tap the Add List button at bottom-left. Give the list an appropriate name, then tap Done. Next tap the new list that you have created; this will open the list editor, where you can add contacts to your list with the Add Contacts button - adding additional contacts as required.

When you’ve finished, you can use the Contacts List(s) that you have created (by name) to address Mail - in the To, cc and bcc fields of your email as required.

You’re very welcome. I’m delighted to have been able help.