Use this option if you want to migrate Outlook messages, contacts, calendar items, tasks, and notes from one machine to another machine. You can create new PST file or import all mailbox items in existing outlook.pst file format.
Now Choose Outlook Data File (.pst) and go ahead with Next Button
Now click in Browse button and select desired files to Import
In options, please select Do not import duplicates option unless you want the imported information to replace or duplicate items already in Outlook.
Now click on Next button and check include subfolder option and Finish