1) Open Settings
2) Open System
3) Tap on Advanced
4) Open System Update
5) If an update is available you should see the update and the option to reboot
After your device restarts, it may show some finishing steps.
After all updates are installed, you should see a message indicating your system is up to date.
Google Documentation: https://support.google.com/android/answer/7680439?hl=en