In Workspace > Email Marketing > Templates, edit the template and under Blocks > Blocks or Content, drag and drop PDF to the template.

Double-click on the PDF content and upload the PDF file. You can select which page to display in the email, if the PDF has multiple pages.

The email recipient can click on the PDF image in the email to view the PDF file.

NOTE: After uploading the PDF document and attaching it to the PDF content, you can click on the PDF content and copy the Source Url. The Source Url can be used with text as an alternative.

PDF as a text link.