Sync iphone on fresh mac

Where is your computer's backup stored on an external drive or some other external media used for backup purposes only, which should include documents, photos, contacts, etc., and your iTunes library?

The iPhone is not designed or intended to be used as a backup storage device.

iTunes includes an option to transfer iTunes content that was purchased/downloaded from the iTunes store from an iPod or iPhone, but this is for iTunes content that was purchased/downloaded from the iTunes store only.

First you need to re-authorize your computer with your iTunes account with iTunes. With your iPhone connected and without syncing, at the iTunes menu bar go to File and select Transfer Purchases From - the named of your iPhone.

Before syncing contacts with the Address Book and calendar events with iCal, enter one contact in the Address Book and one calendar event in iCal on your Mac. This will provide a merge prompt with the first sync for this data, which you want to select.