Your Chromebook automatically checks for and downloads updates when connected to Wi-Fi or Ethernet.
But the Chromebook has to Restart for updates to get applied.
Sometimes the update has already been downloaded and you just need to restart.
For troubleshooting - Update Your Chromebooks Operating System
Next to your account photo
You will see a number of Notifications Click on it
Click on the Notification that says Update Available
Click Restart to apply the Update.
Turn on your Chromebook.
Click your account photo.
Click the Settings gear.
Click About Chrome OS.
Under "Google Chrome OS," you'll see which version of the Chrome operating system your Chromebook is using.
If an update is needed it should begin automatically.
If not, click Check for Updates.
Don't forget to RESTART to apply the update.
