In order to add a PDF you will have to follow the steps below:
- On the left side menu, click on the Media category and click on Upload Files.
- On the new window that opens, in the Upload to section, choose the page where you want the file to be assigned. If you don't want to assign it to a specific page, add it to the most relevant one. Then choose the PDF you want to upload and when the upload is finished press DONE.
- Find the newly uploaded PDF inside the Media Page and click on Edit (pencil icon).
- On the new window that opens find the Media URL and copy it.
Click Save to complete the procedure and publish the website to see your changes.