1. Install a loopback sound driver, like VB-Audio.
You would get a virtual playback device and a virtual recording device. Set the virtual playback device as default.
2. Install and setup Icecast server.
3. Install an Icecast source application. I'm using butt (https://danielnoethen.de/).
Go to butt's settings, and configure the server and stream info. Then go to the Audio tab and set the input to be the virtual recording device, also, increase the audio quality.
4. Listen to the stream on the host machine.