It is relatively easy to upgrade your Ubuntu Linux computer using the GUI. However, if you want to do an upgrade to the next Ubuntu release from the command line or shell prompt, here is the method.
At the command prompt, type the following commands:
$ sudo apt-get update <enter>
$ sudo apt-get install update-manager-core <enter>
$ sudo do-release-upgrade <enter>
Sit back and relax while your release is upgraded.