By default, Outlook uses AutoArchive to archive items at a regular interval. To learn more, see Archive older items automatically. You can also archive items manually whenever you want. That way, you can control which items to archive, where to store them, and how old an item needs to be before it can be archived.
In Outlook, email messages, contacts, calendar items, tasks, and notes can be exported to archive files. You can import these files (.pst in Outlook for Windows and .olm in Outlook for Mac) into Outlook for Mac. Once imported, the archived content can be found in the On My Computer section of the Outlook navigation panes (Mail, Calendar, People, Tasks, and Notes). Notes: