GNU/Linux Ubuntu 20.04 Installing GIMP 2.x – Step by step Guide
How to Install Latest ‘The GIMP’ 2.x on Ubuntu 20.04 Focal LTS GNU/Linux desktop – Step by step Tutorial.
And the GIMP 2.x for Ubuntu 20.04 (GNU Image Manipulation Program) is a Raster Graphics Editor used for Image Retouching and Editing, Free-Form Drawing, Resizing, Cropping, Photo-Montages, Converting between different Image Formats, and More specialized Tasks.
Finally, the Guide include detailed instruction on How to Getting Started with The GIMP on Ubuntu.

1. Launching Terminal
How to QuickStart with Command Line on Ubuntu GNU/Linux
First, Update the Apt Repo Sources with:
sudo apt update
Authenticate with the User Admin Pass.
If Got “User is Not in Sudoers file” then see: How to Enable sudo.
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