Cant link to PDF on contentful. Unable to insert and link to PDF

Contentful editor doesn’t have any button for linking to a file, like a PDF.
I wanted to link like:
“Download the full report here” with the text linking to the PDF, which i’d like to upload, or choose from existing.

My clients, the authors, will need to publish reports every week to disseminate, and at current, wordpress can do this of course I’m surprised contentful cannot.