index.js
import React from 'react';
import ReactDOM from 'react-dom/client';
import './index.css';
import App from './App';
import reportWebVitals from './reportWebVitals';
import axios from 'axios';
// Add a request interceptor
axios.interceptors.request.use(
  config => {
    console.log("inside interceptor request", config)
    const token = "TOKEN FROM INTERCEPTORS"
    if (token) {
      console.log("INSIDE request use")
      config.headers['Authorization'] = 'Bearer ' + token
    }
    
    return config
  },
  error => {
    Promise.reject(error)
  }
)
axios.interceptors.response.use(
  config => {
    console.log("inside interceptor response", config)
    return config
  },
  error => {
    Promise.reject(error)
  }
)
const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(
  <React.StrictMode>
    <App />
  </React.StrictMode>
);
reportWebVitals();
App.js
import logo from './logo.svg';
import './App.css';
import { useEffect } from 'react';
import axios from 'axios';
function App() {
  useEffect(()=> {
    axios({
      method: 'get',
      url: 'http://localhost:1234/webservice.php'
    })
      .then(function (response) {
        console.log(response)
      });
    
  }, [])
  return (
    <>
    This is App component
    </>
  );
}
export default App;
webservice.php
<?php
header("Access-Control-Allow-Origin: *");
// echo "<pre>";
// print_r($_SERVER);
echo json_encode(["test" => "Hello world...."]);