Links, routes, page navigation in React

import { BrowserRouter as Router, Routes, Route } from 'react-router-dom';

https://www.loginradius.com/blog/engineering/react-router-basics/

App.js // do not toutch index.js

https://stackoverflow.com/questions/69832748/error-error-a-route-is-only-ever-to-be-used-as-the-child-of-routes-element