Let’s say you have a page or piece of content in Builder already, but you want to duplicate everything about it and make some modifications. We can do that in a few different ways.
The first way to accomplish that is to click the three dots in the upper right hand corner of the editor:
After clicking on that, a dialog will pop up. Choose Duplicate:
After clicking duplicate, Builder will copy that content entry and create a new one for you with all the same content and targeting.
If instead you just want to copy pieces of content, or just the content and not other settings, you can utilize the upload/download json feature discussed in this forum post.