See the tutorial here https://docs.avaloniaui.net/docs/tutorials/music-store-app/
This project tries to duplicate the steps used in the tutorial, but due to differences in F# and C#, the code may not be exactly the same, especially in F# Async vs C# Task and their differences in multitasking concepts.
Also, the tutorial is quite outdated, there are a few changes in libraries, esp. ReactiveUI.