how to add react js script to my html code? – Blancer.com Tutorials and projects

i have code like this

import React, { Component } from 'react'
import { Button, Container, Modal, Overlay } from 'react-bootstrap'
import TextareaAutosize from 'react-textarea-autosize'
import request from '../helpers/request'
import Pusher from 'pusher-js'
import { URL_API, PUSHER_KEY, PUSHER_CLUSTER, CHANNEL_DEFAULT } from '../configs/keys'
import { getID, setID } from '../helpers/cookies'

const customModal = {
  width: '40%'
}

// class App extends Component {
export default class FloatButton extends Component {
  targetRef = React.createRef()
  messagesEndRef = React.createRef()

  constructor() {

i have try use this code

<body>
    <div id="container"></div>
    <script src="https://*/react-15.0.0.js"></script>
    <script src="https://*/react-dom-15.0.0.js"></script>
<script src="https://js.pusher.com/7.0/pusher.min.js"></script>
    <script src="https://unpkg.com/babel-standalone@6/babel.min.js"></script>
<script type="text/babel" src="FloatButton.js"></script>
    
</html>
  </body>

my question is how to add my java script to my existing html ? because when i run my html i got problem.. can someone help me for fix my issue ?