If you are speaking about converting a Marketo Email into a .pdf, there is nothing native to Marketo that does this. However, you can enable the "Include View as Web Page" link on the email in question and then send this email to yourself. You can then view the email as a webpage in Chrome, and use the Chrome addon "Save as PDF" to convert the page to a .pdf.
*Note that the .pdf will include the appended tracking links in the .pdf. You may want to disable the tracking links via the following solution:
Disable Tracking for an Email Link.