I already updated my IOS but still cannot pair the Apple watch

Re: I cannot pair iPhone 11 to Apple watch

For IPhone with iOS 16 or higher ... seems Apple Watch will need Watch OS9 or higher in order to pair.

Check compatibility: watchOS 9 is compatible with these Apple Watch models:

Apple Watch Series 4 and later

Apple Watch SE (1st generation) and later

Apple Watch Ultra

How to: Update your Apple Watch - Apple Support