Check out example codes for "embed pdf in html w3schools". It will help you in understanding the concepts better.

Code Example 1

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
  </head>
  <body>
    <h1>PDF Example with iframe</h1>
    <iframe src="/uploads/media/default/0001/01/540cb75550adf33f281f29132dddd14fded85bfc.pdf" width="100%" height="500px">
    </iframe>
  </body>
</html>

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