A PWA is your website with superpowers: it installs on a phone straight from the browser, sits on the home screen with its own icon and opens full screen, with no address bar. For your users it's just another app; for you, a single codebase.
The key part is that it keeps working offline. Together we decide what must always be available (the catalog, recent searches, a form that sends itself once the connection is back) and I store it on the device. I also design the icon, the splash screen and the install prompt.
If you want to be on Google Play, I package it as an Android app and take care of publishing it. It's a good fit when your audience comes back often: a shop, a work tool, a game people play every day.