GNU/Linux Xubuntu 20.04 Installing AMDGPU Pro – Step by step Guide
How to Install AMDGPU-Pro Graphics Driver for Xubuntu 20.04 Focal LTS GNU/Linux – Step by step Tutorial.
And AMDGPU Pro for Xubuntu 20.04 includes the AMD Proprietary OpenGL, OpenCL, and Vulkan Drivers.

1. Terminal Getting Started Guide
How to QuickStart with Command Line on Xubuntu 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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