how to report item as lost of stolen?

You report it to local law enforcement. They can put the serial number in the national database of stolen items where any LE agency can spot it should your device turn up in their jurisdiction.

Private companies like Apple do not have access to that database

Apple itself does not take any such reports. They take no active role in searching for, or monitoring or tracking anyone’s personal devices. They provide Find My for you to use, but they take no role in whether your use it or not.

Also note that means Apple will never contact you in any way about your lost or stolen property. Any such message you may receive is a phishing scam and is not from Apple.

If you had Find My enabled, you can use this to track your iPad, as well as erase your personal data and make it impossible for anyone to use the stolen device.

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