4 digit passcode iPhone 14 ?

It is possible, based on this Apple article -> Use a passcode with your iPhone, iPad, or iPod touch

Use a passcode with your iPhone, iPad, or iPod touch - Apple Support

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Set up a passcode

1. On iPhone X and later, or iPad with Face ID, go to Settings > Face ID & Passcode. On earlier iPhone models, go to Touch ID & Passcode. On devices without Touch ID, go to Settings > Passcode. 
2. Tap Turn Passcode On.
3. Enter a six-digit passcode. Or tap Passcode Options to switch to a four-digit numeric code, a custom numeric code, or a custom alphanumeric code.
4. Enter your passcode again to confirm it and activate it.

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