Anytime that I attempt this the entire document is transferred and not in default formatting style.
Please edit your question to better describe what you expect (specification) and how you presently do it (procedure).
Be as precise as possible. Remember we can’t watch your screen from behind your shoulder.
Don’t forget to mention OS and LO version.
It is not directly possible to directly write out a selection of a document to a new file. You can copy the selection, paste it to a new open file and then save that file.
Formatting will be preserved fully if the new file is based on the same template. If you are not sure, then you could copy your current file, erase all its content and past the selection in there (or alternatively, delete anything you do not want to include in the new file.