The new IosMac does not have itunes and i need to restore a phone. What can i do?

Use Finder: What happened to iTunes? – Apple Support (AU)

As a reply to the above post all features of iTunes for iPhone and iPad syncing have been relocated to finder. To restore for IPSW shift click the restore iPhone button and select the file.

Do you need to restore from a backup or from an IPSW/firmware file?