Drive locked and forgot the password

From the official Apple website If you can't reset your Mac login password

1. Shut down your Mac. If you can't shut down normally, press and hold the power button for up to 10 seconds, until your Mac turns off. (Every Mac has a power button. On laptop computers that have Touch ID, press and hold Touch ID.)
2. Press and hold the power button on your Mac. As you continue to hold the power button, your Mac turns on and loads If your Mac starts up to Options with a gear icon. When you see Options, release the power button.
3. Click Options, then click the Continue button that appears below it.

After clicking "Forgot all passwords?", if you're asked for your FileVault recovery key:

1. Enter your FileVault recovery key. You received it when you turned on FileVault and chose to create a recovery key instead of allowing your Apple Account to unlock your disk.
2. When prompted to reset your password, click Reset Password.
3. Select a user to reset the password for.
4. After successfully authenticating, click Exit.
5. Choose Apple menu > Restart, then log in with your new password. Password reset is now complete. You don't need to take additional steps.

If you frogot or don't have your FireVault Key, I'm sorry You have lost your data. There is no way to get your FireVault key without logging into the Mac.

Happy iFixing.

Is this the password for the laptop alone? If you forgot your Mac login password

If it is just the drive alone then Enter a password to unlock the disk macintosh hd - data which I believe means you are sadly out of luck :(