blank page and error after deploying react app to a server

I created an app using react js , then i deployed it to a server but when i access it i found a blank page with no error message . I searched google and other related issue in stackoverflow and i tried their solution but I still have the blank page . then I changed BrowserRouter to HashRouter in this case it works but at some point the following error appeared : error message image

( i think i can fix it with few changes in the code )

but I don't want to use HashRouter , is there any other possibility to make it work ( no blank page ) using BrowserRouter ?

package.json :

{
  "name": "flowdia_react_version",
  "homepage": ".",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "@testing-library/jest-dom": "^5.11.4",
    "@testing-library/react": "^11.1.0",
    "@testing-library/user-event": "^12.1.10",
    "react": "^17.0.2",
    "react-dom": "^17.0.2",
    "react-router-dom": "^5.2.0",
    "react-scripts": "4.0.3",
    "serve": "^12.0.0",
    "web-vitals": "^1.0.1"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build",
    "test": "react-scripts test",
    "eject": "react-scripts eject"
  },
  "eslintConfig": {
    "extends": [
      "react-app",
      "react-app/jest"
    ]
  },
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  }
}

index.js :

import React from "react";
import ReactDOM from "react-dom";
import App from "./App";
import { BrowserRouter as Router } from "react-router-dom";

ReactDOM.render(
  <React.StrictMode>
    <Router forceRefresh={true} >
      <App />
    </Router>
  </React.StrictMode>,
  document.getElementById("root")
);

app.js :

import "./dist/css/style.css";
import { Switch, Route } from "react-router-dom";
import Questions from "./components/questions/Questions";
import StartPage from "./components/StartPage";
import Output from "./components/Output";
import HomeCare from "./components/HomeCare";


const App = () => {
  return (
    <Switch>
      <Route path="/" exact children={<StartPage />} />
      <Route path="/questions" children={<Questions />} />
      <Route path="/output" children={<Output />} />
      <Route path="/home-care" children={<HomeCare />} />
      
    </Switch>
  );
};

export default App;