X86 Odyssey Help Install PCIe GPU on Debian Stretch

Hello, I’m new here. Sorry if this is in the wrong community.
I have a Debian 9 build on my x86 odyssey and I needed some help on how to install it. I followed the instructions on the adding accessories page but once the topic started to mention ubuntu I could not continue. If anyone knows what I should do next to install my amd radeon GPU on debian 9, I would greatly appreciate it! Thanks!

Installing GPU on linux is slightly more tricky, can you provide your exact verison of GPU?