react redux with initial state

App.js

import React from 'react'
import { Provider, useSelector, useDispatch } from 'react-redux'
import { createStore } from 'redux'


function Counter() {
  const count = useSelector(state => state.count)
  const dispatch = useDispatch()
  const action = {
    type: "ADD",
    count: 1
  }

  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => dispatch(action)}>
        Click me
      </button>
    </div>
  )
}

function reducer(state, action) {
  if (action.type === "ADD") {
    return {
      count: state.count + 1
    }
  }

  return {
    count: 0
  }
}

const initialState = {
  count: 0
}
const store = createStore(reducer, initialState)
function App() {
  return (
    <Provider store={store}>
      <Counter />
    </Provider>
  )
}

export default App