It’s dumb, but for some reason I can never find the Ubuntu Raspberry Pi images when I google for them, so I’m sticking the links here:
Worth a mention: Ubuntu 22 supports Raspberry Pi 4B but not 5. Official Ubuntu support for Raspberry Pi 5 starts with Ubuntu 24.04. If you have something (like ROS) that depends on Ubuntu 22, you’re going to have to get creative to run it on the Pi 5, or port it forward.