Install this control panel on the Windows PC and access it via this path: Start Menu -> Control Panels -> iCloud. It can and will be done via Apple’s iCloud Control Panel for Windows (Windows Vista SP2 or Windows 7 or later required). He wants to sync the calendars in the two Apple products with Outlook on the PC.
My son-in-law has a Windows PC and uses Outlook. Thomas Staton is attempting to help a wayward relative.