GNU/Linux Ubuntu 20.04 Install Radeon RX 580 Driver
Hi! The linked Tutorial shows you Step-by-Step How to Install AMD Radeon RX 580 Graphics and GPU Driver for Ubuntu 20.04 Focal LTS GNU/Linux 64-bit Desktop.
And there are 2 Radeon RX 580 Ubuntu Focal Graphics and GPU Driver available Alternatives: the AMDGPU Pro and the AMDGPU Open-Source.
Moreover, the AMDGPU Pro Software includes Support for Accelerated Graphics, MESA Multimedia, Pro OpenGL, Pro Vulkan and Pro OpenCL.
Especially relevant, the Latest Driver supporting a Device varies over Time, so before the Setup you should check:
Finally, for the Radeon Open Source Drivers on Repo See instead: How to Install AMDGPU from Ubuntu PPA.
AMDGPU Ubuntu 20.04 Installation Guide