To use Oberon, you need an extra device on the same local network as your Xbox console. This device is referred to as the "remote" or the "input server". It takes inputs from your controller, (eg. a Dualsense), and sends it to your Xbox with websockets.
Some apps and games may not work properly with Oberon Remote Input. Apps are able to detect and block synthetic inputs so there's no guarantee that everything will work smoothly in all situations. Some emulators like Retroarch and XBSX2 don't work with Oberon. Competitive games like Fortnite and VALORANT seem to work for now.
