With iOS 18, the Phone app has been upgraded in a few different ways.
T9 dialling is the most obvious new feature, and its addition will please many iPhone users are have been accustomed to having that feature on their previous Android handsets.
To use T9 dialling on iOS 18, simply go to the Keypad in the Phone app. Dial in the numbers corresponding to the first few letters of the person’s name you wish to call. Each number button represents three or four letters, so just press the relevant number.
iOS will automatically filter the address book to find possible matches. The matching person’s name and number will appear at the top of the screen. Tap on the name to confirm and initiate the call.
https://9to5mac.com/2024/06/10/ios-18-adds-t9-dialling-iphone/