1. Select or open a Google document that you wish to download as a PDF.
2. Go to “File”, next click “Download as” and finally choose “PDF Document”.
3. It should download into your Downloads or it will have an option to save into your desired folder. Find the file in the folders and open up your PDF to make sure it will successfully open.
Or Watch Convert Google Docs to PDF Tutorial (2-minute video), which illustrates how to open a Google Doc from Drive and Export it as PDF.
Reference: How to Export a Google Doc to PDF