Applying General Non-Fiction format to existing content

Hello All, Is there a way to easily retrofit existing content into the “General Non-Fiction” book format? Conversely, is there an easy way to take that preset book format and recreate it onto the existing content of a manuscript that is all but complete. My objective is to facilitate the compile and printing process. I have the content of multiple books organized within one Draft folder, where each book shares much of the content but also has its own content that I plan to “assemble” at the point of compile. Is there are better way in which I could approach the end stages of my writing project? I am using Scrivener version 3.01.