The short answer is to choose Apple's 30W USB-C power adapter, which at $39 is the company's lowest-priced charger that can charge the iPhone 14 and iPhone 14 Pro Max at their maximum supported charging speeds of 25W and 27W, respectively. All other higher-priced Apple chargers, such as the new 35W adapter with dual USB-C ports for $59, charge the devices at equal to negligibly faster speeds at best.
The correct answer should have been to just use what you already have instead of buying a new adapter because doing so is bad for the environment (according to Apple) and that's why Apple doesn't include it in the box anymore.