Hello Joseph,
The encrypted volume will not longer be accessible and the computer will not be able to start without either recovery key or recovery password. If you lose the USB flash drive, you might manually input the recovery password.
Recovery Key (Startup Key): The recovery key can be created and saved to a pluggable USB flash drive during BitLocker setup; furthermore, it can be managed and copied after BitLocker is enabled. By inserting a USB flash drive containing the recovery key into the computer when it starts, the user is granted access to the operating system volume regardless of the state of the TPM.
Recovery Password: The recovery password is a 48-digit, randomly generated number created during BitLocker setup. It can be managed and copied after BitLocker is enabled. Through the interface, the recovery password can be printed and/or saved to a file for future use.
According to your current situation, I suggest you directly printing the recovery password out as a backup. Once the drive is locked, you can only boot to recovery mode; if you could not get the USB flash drive (recovery key) available, you might enter the recovery password through your keyboard.
Hope the above information helpful!
