Missing Folders: extensions, js, post-formats

I updated Builder:Air using this tool and agreed to let it set up my functioning folder as Builder-Air-Custom.

I’m trying to use Builder “extensions” for the first time and none work, as set up in my Layout. I looked at the directories and there is no “extensions” folder in my Builder-Air-Custom folder! Also, no “js,” nor “post-formats.”

Should there be or should there not be?

If I move them over, should I delete them from the vanilla Builder-Air folder? (I did and it didn’t help.)

There are just too many variables for a beginner to deal with, to understand why my chosen extensions are not working! But that’s beside the point. What in the world should I do about these three folders?

https://ww.wp.xz.cn/plugins/easy-theme-and-plugin-upgrades/