How can I update my iPhone to new version

Chances are, you already have the latest update that your phone is qualified to receive.

To check, tap Settings, tap General, tap Software Update.

If your phone is qualified for an update, the update option will appear.

shirinbafekr21 wrote:

How can I update my iPhone

You don't your phone isn't compatible iOS 16 and iPadOS 16 are compatible with these devices - Apple Support

buy a newer iphone outlined in the blue link to to get the new ios