IOS – 2FA code sent to wrong unknown number (Iran)

The message you describe is what happens when a locked phone is restored by iTunes without a SIM present from the carrier that the phone should be locked.

You could use any of the IME I look up tools on the Internet- some are free and some are paid and all make me worry they are harvesting databases of IMEI/serial number/other data in exchange for providing you a service by looking up your phone in the carrier database.

Of course, you can always contact the carrier in question to see what is needed to get service or a Sim card for that device.

Activation through iTunes or Over the Air (OTA) is when the device checks to determine if it is factory or carrier unlocked or if it needs a SIM to be activated.

It's almost certain that your failure to activate is due to not having a SIM card from the proper carrier. You do not need to have an active contract or phone number associated with the SIM (I have a 3GS which has an old SIM without a plan), it just has to be for the correct carrier.