Set both icons & a manifest in your package, then submit it to the Microsoft Store.
This site is useful when publishing a Progressive Web App (PWA) to the Microsoft Store. Applications available on the Store are “Universal Windows Platform (UWP) apps”.
With this site, you can transform your PWA metadata to the UWP format spoken by the Store. A recent browser suffices for the job. You won’t need Visual Studio, or even Windows 10 😉
A (web) app installed via the Microsoft Store has access to all the WinRT APIs. It’s not just a glorified bookmark, like on other platforms — Google may advertize this as “progress(ive)”, the fact is that Apple made it possible with the very first iPhone, in 2007!