Earthyyy When I tap on "Check for updates", nothing happens.
First step of troubleshooting: Have you tried turning it off and on again? Sometimes an OTA update has already been installed and is waiting for you to reboot into it. You should be notified but sometimes users swipe off the notification and forget about it. Also as a general recommendation you should reboot anyway every once in a while. Some people don't reboot in many months.
Earthyyy Thanks! Just now confirmed. My phone has ***1900 and the latest is ****2700. So
how do I trigger the update? Or it can only be done via OTA or auto update? Im a non technical person so forgive me if this is a dumb question.
When the GrapheneOS project announces a new release is published, it only means it's available for download by anyone who wants it, not that it has reached the Stable update channel and pushed to everyone. See:
https://grapheneos.org/releases#release-announcements
https://grapheneos.org/releases#about-the-releases
https://grapheneos.org/usage#updates-sideloading
Edit: And your question isn't dumb :)