The iOS 16.3, iPadOS 16.3, and macOS Ventura 13.2 betas that were provided to developers today introduce support for physical security keys that can be used as extra protection for an Apple ID.
Apple announced the new feature last week, and said that it would be introduced in 2023, which lines up with when we are expecting the launch of iOS 16.3 and its sister updates. Security Keys for Apple ID will provide users with the option to add a third-party security key to their account, which will be needed for authentication when logging into a new device or otherwise accessing an Apple ID.
The Security Key is designed to replace the verification codes that are sent to Apple devices when logging into another device, which is the standard method of authentication that Apple uses. Apple says that physical security keys provide strong protection against phishing and unauthorized account access.
Security Keys can be set up on devices running the beta by going to Apple ID > Security Keys and following the instructions. The iPhone, iPad, and Mac support FIDO Certified security keys.
Source: Macrumors