You have a few different options to publish your app. You can download the files and deploy them to your site, or you can download pre-populated app projects for the major app platforms from the links below.
Service Worker support requires RS4 or above. You'll get a copy of each PWAbuilder component as well as a side-loadable version of your PWA (requires Win10 in dev mode). The Generate Appx button can be used to generate a PWA package to submit to the Microsoft Store.
You can use Xcode to build this package to produce an app that runs on MacOS.
PWAs are available through the browser on Android, however your PWA can also be submitted to the play store by submitting the package you get below.
PWAs are avaiable through the browser on iOS, however your PWA can also be submitted to the app store by building the package you get below in Xcode.