How to connnect my carrier to my apple

If you don't have a SIM card in the phone, look for / visit a carrier, take a subscription, postpaid or prepaid card.

Check whether the SIM card is suitable for your iPhone.

Hopefully you have an carrier unlocked iPhone.

See also ⤵️

If you can't activate your iPhone or iPad (Wi-Fi + Cellular)

If you can't activate your iPhone or iPad (Wi-Fi + Cellular) - Apple Support

How to unlock your iPhone for use with a different carrier

How to unlock your iPhone for use with a different carrier - Apple Support

• Apple can't unlock your iPhone for use with a different carrier. Only your carrier can unlock your iPhone.

You need to contact your Carrier.

Or do you need the PUK code?, See this Apple article: Use a SIM PIN for your iPhone or iPad

Use a SIM PIN for your iPhone or iPad - Apple Support