Ref: https://www.makeuseof.com/tag/raspberry-pi-update-raspbian-os/
- Begin by updating the repository package list:
sudo apt-get update && sudo apt-get upgrade - When this is done, run the upgrade command:
sudo apt-get dist-upgrade - Follow any prompts and wait for the Pi to be upgraded. When you’re done, type:
sudo apt-get clean - This will discard any unneeded files that have been downloaded as part of the upgrade. Finish by restarting:
sudo reboot