Try posting at a linux Forum like Phoronix: https://www.phoronix.com/forums/forum/software/mobile-linux/1258447-benchmarking-amd-ryzen-5-5500u-l...
Here is AMD 5500 VGA Driver with Linux driver to download: https://www.amd.com/en/support/graphics/amd-radeon-5500-series/amd-radeon-rx-5500-series/amd-radeon-...
But looking at the "Release Notes" from Ubuntu and only shows Desktop GPU cards and no mobile APUs compatibility.
According to this Linux website on how to install AMD Radeon driver it mentions that some Linux OS has native drivers for AMD GPU already. But it shows you how to tell if the AMD Linux driver will support your graphics or not: https://linuxconfig.org/amd-radeon-ubuntu-20-04-driver-installation
But here is a AMD website that gives you step by step instructions on how to install AMDGPU-PRO driver: https://amdgpu-install.readthedocs.io/en/latest/
NOTE: According to Phoronix article that I linked there are 5500U compatible drivers in Linux drivers.
