Check out example codes for "how to add jquery to html". It will help you in understanding the concepts better.

Code Example 1

<!--You can insert Jquery into HTML with the <script> tag.-->
<head>
  <script type = 'text/javascript' src = 'https://code.jquery.com/jquery-3.3.1.js'></script>
</head>

Code Example 2

<head>

<script src="https://ajax.aspnetcdn.com/ajax/jQuery/jquery-3.4.1.min.js"></script>

</head>

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