React not able to fetch data from Node APiI

Question

I have made an API in Node and can see the data using Postman and by hiting the endpoint in the browser. But, when I try to fetch it using React, I can't see it and am getting few errors. one of them is related to the CORS, which I tried to solve by adding a proxy in the package.json of the client folder but it's still not getting solved. Here's my code:

Error:

img

App.js

import React, { useState, useEffect } from "react";
import "./App.css";

//Pages

//components
import Navbar from "./Components/Navbar";
function App() {
  let initialData = [];
  const [data, setData] = useState(initialData);
  const [isFetched, setIsFetched] = useState(false);

  useEffect(() => {
    let headers = new Headers({
      "Content-Type": "application/json",
      Accept: "application/json",
    });
    fetch(`http://localhost:4000/`, headers)
      .then((res) => res.json())
      .then(
        (result) => {
          setData(result);
          setIsFetched(true)
          console.log("result"+result)
        },
        // Note: it's important to handle errors here
        // instead of a catch() block so that we don't swallow
        // exceptions from actual bugs in components.
        (error) => {
          console.log(error);
        }
      );
  });

  return (
    <div className="container">
      <Navbar data={data} isFetched={isFetched} />
    </div>
  );
}

export default App;

NodeJs code:

const router = require('express').Router();

router.route('/').get((req, res) => {
    let displayData=[{
        user:'a',
        id:1
    },
        {
        user:'b',
        id:2
        }
    ]
    res.status(200).json(displayData);
    res.send("<h1>Home</h1>")
})

module.exports = router

server.js:

const express = require('express');
const cors = require('cors');
const { pool } = require("./db/dbConfig")
const app = express();
const port = process.env.PORT || 4000;

const homeRouter = require("./routes/home")


//middleware

app.use("/", homeRouter);
app.use(cors());
app.use(express.json());

app.listen(port, () => {
    console.log(`We are live on port: ${port}`);
});