Hello
BitLocker Drive Encryption provides an option to use a smart card to unlock BitLocker-protected data drives on your computer. However, the option to use a smart card to unlock the Operating System (OS) drive is not directly available in BitLocker. This is due to the way BitLocker is designed. The OS drive needs to be unlocked very early in the boot process, at a point where the necessary drivers to read a smart card are not yet loaded.
There are some workarounds that you can consider:
Using a Startup Key: You can create a startup key that is stored on a USB device. When you start your computer, you insert the USB device that holds the startup key, which unlocks the OS drive. This isn’t exactly the same as using a smart card, but it provides a similar level of two-factor authentication.
Using a TPM with a PIN: If your computer has a Trusted Platform Module (TPM), you can configure BitLocker to require a PIN to be entered during startup. This provides something you know (the PIN) and something you have (the TPM) as factors for authentication.
Third-Party Solutions: There are third-party solutions that can enable the use of a smart card to unlock the OS drive. These solutions integrate with BitLocker and add the ability to use a smart card for pre-boot authentication. However, these are typically enterprise solutions and may not be suitable for individual users.