How to download pdf from pdfdrive programmatically?

Question

I am trying to create a program that can download PDF automatically from the site "www.pdfdrive.net" but cannot get the PDF link from the site because they are using AJAX calls.But when I am using Mozilla Firefox, it is giving me the download link when using "Inspect" but not on "View Source".How can I download the PDF from the site???What I have tried: I have tried to use the default web browser to navigate to the page but it becomes unable to load the downloading link. For more details of what I tried goto : https://www.codeproject.com/Questions/1223157/How-do-I-download-pdf-from-pdfdrive-net-automatica