How to install the Oracle Virtual box on Ubuntu
Step 1: Update the package repository in Ubuntu before setup Virtual box
sudo apt update
Step 2: Download and install VirtualBox by running:
sudo apt install virtualbox
Step 3: Install the VirtualBox Extension package for support USB, Disk encryption etc
sudo apt install virtualbox-ext-pack
During installation VirtualBox ask to accept PUEL License and select Ok.

Accept the PUEL license by selecting Yes.

After accept the license, it start again and show the message os successfully installed ” Oracle VM VirtualBox Extension Pack”

Open the Virtual Box Software by typing command :
virtualbox