To recover your Apple Watch from an iCloud backup follow these steps:

1. Select the Watch app from the menu.
2. Start Pairing by pressing the Start button. If you want to link a second Apple Watch, tap your existing Watch at the top and select Pair a new Apple Watch.
3. Tap Restore from Backup after the Watch has synced.
4. Select the backup that you want to restore.

I hope this answer helps you

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