How to make an existing VueJS + Ionic4 + Capacitor app a PWA

I am little confused with documentation.

In documentation to add iOS we need to run
npx cap add ios

But I am not sure what I need to do to add PWA support to my app.

In Capacitor docs it is told that I just need to add below code to make a PWA app. And after build I need to serve my dis folder npx cap serve
import { Capacitor } from '@capacitor/core';

But on doing npx cap serve I am not seeing any manifest file or service worker in developer tools.

Am I missing anything?

My capacitor.config.json looks like this

  "appId": "net.b*********",
  "appName": "***********",
  "bundledWebRuntime": false,
  "webDir": "dist",
  "ios": {
    "minVersion": "11"

Do I need to create my own service worker and manifest files so that splash screen and icons of PWA can be configured or Capacitor itself does that?