Create a left-hand link to a PDF
While you can't link directly to a PDF when creating a left hand link, there is a work around. You can generate a URL to the PDF, and then create an external section link to the PDF.
To do so:
Open any page on your site in direct edit:
Click anywhere in a content block, and then click the "insert file link or image" icon.
Locate the PDF in your media library and click directly on it
This will embed a link to the PDF on your page:
Save and approve this change so it publishes on your site, wait for the link to appear on your page (it can take up to 1o minutes to appear), and then click on the link:
Doing so will open the PDF in your web browser.
You can now copy the URL to this PDF:
Use this URL to create an external section link