Here the latest RX580 Driver version from AMD: https://www.amd.com/en/support/graphics/radeon-500-series/radeon-rx-500-series/radeon-rx-580
Sounds like the AMD Driver didn't install correctly. The OpenGL box should be filled in GPU-Z.
Download the latest version from AMD. Delete the AMD Folder at C:\AMD. Download the latest version of DDU and run it either from the Windows Desktop or from Windows Safe mode (recommended) with the INTERNET DISCONNECTED!.
After DDU finished delete all traces of AMD driver and boots back into Windows Desktop. Run the full AMD Driver package that you downloaded, still with the internet disconnected, and install it.
Once it installs correctly, reconnect the internet and check to see if GPU-Z OpenGL is checkmarked now. Also delete again the AMD Folder at C:\AMD to prevent future corruptions of AMD driver installs and to save space on your HDD/SDD.
