1. Go to site builder open file manager.
  1. Upload PDF file here and copy link of uploaded file.
  1. Now go to pop-up and add custom pop-up.
  1. When pop-up open click on this + sign and add custom code in Pop-up.
  1. This window will appear add custom code here.

Here is the code:

<object data="test.pdf" type="application/pdf" width="300" height="200">

alt : <a href="test.pdf">test.pdf</a>

</object>

You need to put your copied code at the place of �test.pdf" which you copied while uploading file as mentioned above. And before that copied code you have to add https://app.flowtrack.co at the place of test.pdf and save it.