It might not be a good idea to do this if you don't own that content in those PDFs. I am assuming you are using copyrighted work of other authors for which you can be served a copyright notice. On the minimum, you can get a violation notice on YouTube and in the worse case, you might also get a court case for copyright infringement.
Still, to answer your question, you will find many tools that can do this online. You don't need to install any application, just upload the PDF file, select the presets for your video and hit the Convert button. Your video will be ready for download in a few seconds.
One website that I could find that does this is - https://video.online-convert.com/convert/pdf-to-mp4