If you are running the server version of Ubuntu or choose to not use the GUI, then you can use this tutorial to upgrade your system to the latest version (or the latest LTS version).
Although many systems can be upgraded in place without incident, it is often safer and more predictable to migrate to a major new release by installing the distribution from scratch, configuring services with careful testing along the way, and migrating application or user data as a separate step.
In Ubuntu, XAMPP will not auto start on boot or reboot in usual Installation. We should manually enter the command to start the XAMPP as SUDO user.
But in the case of a standard user in Ubuntu, he cannot use the sudo command as he doesn’t have the admin privilege. In many cases like computer labs where students should not be provided with the admin privilege have to use XAMPP server for their academic needs.
The solution is as given below. Once you do this solution as a privileged user, XAMPP starts automatically while booting into your system (even if you are using unprivileged standard user).