This video tutorial is about upgrading previous version of Ubuntu to Ubuntu 20.04 LTS (Long term support version), in fact it is a fresh installation without losing files.
Why fresh installation, instead of upgrade?
Upgrading is may times painful, even though canonical made the ubuntu upgrade as easy as possible, some times it is buggy due to lot of open source software we already installed on it. Also, it is time consuming process. Fresh installation makes you feel like you have got a new House.
Please make sure you have installed '/home' as separate partition in your previous installation, otherwise you will lose files. You can find it using lsblk command.
If you do not have /home as separate partition or installing Ubuntu a fresh, please see our another video :
https://www.youtube.com/watch?v=BDSPh9U02_c
Please back up the configurations or files if you have at root partition before proceeding for fresh installation.