GNU/Linux Ubuntu 20.04 Installing VirtualBox – QuickStart Guide
Hi! The Tutorial shows you Step-by-Step How to Install the Latest Oracle VirtualBox 7.x in Ubuntu 20.04 Focal LTS GNU/Linux Desktop.
And Oracle VirtualBox for Ubuntu Focal is a powerful PC Virtualization solution allowing you to run a wide range of PC Operating Systems on your Linux platform. This includes Windows, Linux, FreeBSD, DOS, OpenBSD and others.
Moreover, Oracle VirtualBox comes with a Broad Feature Set and Excellent Performance, making it the premier Virtualization software solution on the market.
Finally, this guide includes detailed instructions about to Install VirtualBox Extension Pack on Ubuntu.

1. Launching Terminal
How to QuickStart with Command Line on Ubuntu GNU/Linux
Here Bash Shell Ubuntu QuickStart GuideLink to Step-by-Step Guide on Getting Started with Command Line in Ubuntu GNU/LinuxFirst, Update the Apt Repo Sources with:
Authenticate with the User Admin Pass.Copysudo apt update
If Got “User is Not in Sudoers file” then see: How to Enable sudo.