How can I enable Apple Intelligence on my iPhone 16 Pro?

See how here, and make sure you read ALL of this and make changes accordingly --> How to get Apple Intelligence - Apple Support (CA)

A few things to keep in mind:

• Language and Siri language is important.
• Apple Intelligence is not yet approved for use in the EU. And if your iPhone was manufactured for a China market, it doesn't matter where you live, you can't have Apple Intelligence until or IF it is ever approved for China.

If the model of your phone ends in CH/A, then it was intended for sale in the China market and currently that region does not allow devices intended to be sold there to have Apple Intelligence. If that is not the case for you, then follow the steps provided here and describe what has not worked along with the region/language that is set on your device.

How to get Apple Intelligence - Apple Support