Forgotten password/missing Recovery Key/FileVault turned ON

That's a reasonable assumption unless you maintain your own separate backups. Going forward, consider keeping your own backups. iCloud is not a backup service but a synching service. If you have other devices, then perhaps your photos are available from them. A Time Machine backup may not be useful, if it, too, was encrypted with a lost recovery key. I would not depend on one backup.

That’s the point of FileVault. Don’t forget your password!

Hi photocg,

FileVault is full volume encryption. Everything, including macOS itself, is scrambled in such a way that you either need your password or your recovery key in order to unscramble it. Without either of these, unfortunately your data might not be recoverable.

When you first set up FileVault, did you store the recovery key in iCloud? You can find out via these steps:

1. Power on your Mac, and wait at the login window for at least one minute.
2. When a message appears at the bottom of the screen, press and hold the power button (or Touch ID) until your Mac shuts off. Then, press the power button (or Touch ID) again.
3. Your Mac will start up to the Reset Password Assistant. Select "I forgot my password".

If you then see the option to sign in with your Apple ID, follow the onscreen prompts. Your recovery key is stored in iCloud, and your Apple ID can be used to unlock your Mac and reset your user account password.

If you're asked to enter a recovery key instead, unfortunately your data might not be recoverable.

Did you make a Time Machine backup before you forgot your password?

Unfortunately, yes, unless one of the below applies:

• You made a backup of your Mac before forgetting your password.
• You enabled iCloud Photos before forgetting your password.

My advice for now would be to keep your encrypted data intact. Take some time to think about the situation; revisit some previous memories, and try to recall the login password. When you're certain, try entering it.

If your MacBook Pro was made in 2018 or later, use your attempts carefully. The T2 Security Chip will start imposing time-based delays after 15 attempts, and will lock out after 30 attempts. 10 more attempts are available in macOS Recovery before having to rely on the recovery key. (Page 52 of this whitepaper)

Also, did you try my steps above? Did it offer the option to sign in with your Apple ID?

How to find your FileVault recovery key in macOS