Is there a way to force a form's PDF to fit onto one page?

My understanding is that you want the PDF submission layout to limit into a single page only.

You can do that by setting the Question Alignment to "Top". In the PDF Editor, click the Layout Settings button and go to Customize tab where you'll see this option.

After that, you can adjust the width of each field and move it towards the other fields so it'll look like you have 2 columns.

Hope that helps. If this is not what you're referring to, let us know.

I know how to do this. Ideally I'd like to keep my layout as is. My question is if I can make the PDF fit on one page. Similar to what can be done in other programs. 

When I checked your PDF layout on this form, I can see that it has 2 pages. The 2nd page occupies the File Upload field. You can adjust the File Upload field into a smaller field using the PDF Editor. In this way, the uploaded image will be smaller and the PDF will be a single page.

Just to clarify, the only way to limit the number of PDF pages is by adjusting the layout (font size, field position, field alignment, field size, PDF margins).