To begin, head to the Website tab and select your site.
1. Create a page or edit an existing page.
2. Upload the .pdf to the Files tab.
3. Once it uploads, right click the file to open the .pdf in a new tab and copy the URL.
4. Go to the Content tab and enter in some text to link the PDF to, i.e. "Open the PDF." Next, highlight that text, and click the link button to enter the URL you copied from the Files tab.
Press Save Content.
It will look something like this your website: