I am making a handbook, and would like to easily make the sections of it separate. How would I be able to do it nicely? mean entirely separate, just in the same document, as for ease of printing
Probably you want to take a look at LibreOffice Help - Working with Master Documents and Subdocuments
If you mean sections as in the Microsoft Word meaning of sections, then Insert > More Breaks > Manual Break will allow you to choose a different page style and reset page numbering.