This article explains how to convert a Google Doc to PDF. The Google Docs website provides a few ways to do this depending on what you want to do with the PDF after it's been converted.

Editing a PDF in Google Drive isn’t overly difficult, and our guide will help you every step of the way.

Open Google Docs. If you're not logged in to your Google account, you'll need to do that now. Select File > Download > PDF Document (.pdf). Save the PDF to your computer.