https://askubuntu.com/questions/99834/how-do-you-see-what-packages-are-available-for-update

/usr/lib/update-notifier/apt-check -p

https://askubuntu.com/questions/49958/how-to-find-the-number-of-packages-needing-update-from-the-command-line

$ sudo cat /var/lib/update-notifier/updates-available

The normal way to upgrade:

$ sudo apt-get upgrade

The alternative way (to use when the normal way above does not completely update everything???):

$ sudo apt-get dist-upgrade

dist-upgradein addition to performing the function of upgrade, also intelligently handles changing dependencies with new versions of packages; apt-get has a “smart” conflict resolution system, and it will attempt to upgrade the most important packages at the expense of less important ones if necessary. So, dist-upgrade command may remove some packages. The /etc/apt/sources.list file contains a list of locations from which to retrieve desired package files. See also apt_preferences(5) for a mechanism for overriding the general settings for individual packages

to retart/reboot the system:

$ sudo reboot