You can use a NextDNS configuration profile at https://apple.nextdns.io and a NextDNS account to block the device communicating with many Apple services.
A good way to disable iMessage and iTunes, though, is to simply not have an Apple ID. (This prevents the install of applications via the App Store, however.) You can of course set up the device with no Apple ID and then only add the Apple ID to the App Store (and not iTunes or iMessage/FaceTime/iCloud). This is what I do.
A good way to disable iMessage and iTunes, though, is to simply not have an Apple ID. (This prevents the install of applications via the App Store, however.) You can of course set up the device with no Apple ID and then only add the Apple ID to the App Store (and not iTunes or iMessage/FaceTime/iCloud). This is what I do.