Although there isn't a direct feature to create borders on Google Docs, there are 3 workarounds that you can use to create that appearance.

How to Put Borders Around Pictures on Google Docs. Google does not offer a feature that directly supports adding borders around the images inserted into a Google Docs document, as of May 2013.

Borders are manipulated using the "Borders" setting in Spreadsheets, and modifying table properties to make borders invisible in Documents or Slides is simply a matter of changing their color to ...

To hide 0r remove borders in Google Sheets and Docs, open the document, select the preferred table, then choose the relevant options to delete the borders.

If you are in the process of writing a novel and you prefer using Google Docs, here is how to format your manuscript to look more like a book.