Make sure your MacBook supports Auto Unlock with Apple Watch
Sign in to the same Apple Account on both devices
Turn on Wi-Fi and Bluetooth on both devices
Turn on two-factor authentication for your Apple Account
Set a passcode on your Apple Watch
Set a password on your MacBook
On MacBook, go to System Settings
Click Touch ID & Password or Login Password
Turn on Use Apple Watch to unlock apps and your Mac
On Apple Watch, make sure Wrist Detection is enabled
Keep Apple Watch unlocked and on your wrist
Wake your MacBook and move near it with your Apple Watch
Authenticate on the MacBook if prompted