When it comes to JQuery, Bootstrap, and Fontawesome, it's important to understand that they are not standalone software or applications that you install on a webpage. Instead, they consist of CSS and Javascript files that function similarly to any other custom code you may have created for your website. The difference lies in the fact that these files are professionally maintained, optimized, and specifically designed for certain functions (for example, Bootstrap specializes in creating responsive webpages).
In order to incorporate these files into your webpage, all you need to do is instruct the HTML file to utilize them by linking them using the <script> tag along with its src* attribute. (*Check out this W3schools link for more information).
By providing a URL in the src attribute, you can point to an online location hosting the file, or alternatively, you can use a relative local path on your server or personal machine where the file is stored. It's possible to manually move the files to your css/js folder and include them using the designated path without the need for specialized software. Placing the file in one central location allows easy access for your entire webpage and its sub pages. This process isn't overly complicated.
CDNs host these types of files for public access for various reasons such as better performance. They also prioritize security measures to ensure safe access to their hosted files. Utilizing CDNs enhances webpage performance as explained in this resource.
Update:
To include files in your HTML, follow this format (using Bootstrap as an example) :
<link rel="stylesheet" href="static/bootstrap/css/bootstrap.min.css">
<script type="text/javascript" src="static/bootstrap/js/bootstrap.min.js"></script>
You simply need to specify the path to the necessary CSS and JS files. For Bootstrap, including these two files provides full functionality of the library.