How do I edit pdf files (created by Adobe) using Libre Office?

I am using Libre Office version 5.3.7.2 (x64)

How to create a pdf file while in Libre Writer?

Open the PDFs working on LO’s surface (File menu > open) ore other adequate proceeding. Draw starts and you can hope (!) that the PDF’s format is readable and editable. Sometimes the layout will be disturbed. The better choice is Adobe Writer, but this is not for free.

Yes. Draw opens the file but the layout/format is disturbed.

You can create PDF files using the File Menu → Save as then choose PDF.
To edit PDF files you have to use LibreOffice Draw. Simply open the PDF file from Draw file menu and you can edit it.

Detailed guide is available here:

Well it is not really that simple. LibreOffice does not “edit” a source PDF. It will filter import it, either as single page image (currently defaulting to the first page of a multi-page PDF, requiring you to split the PDF externally) or by filter will split out the objects and text runs of the PDF presentation and place those discrete Draw objects with some level of fidelity to the original PDF. That can be into the Draw module by default–or into Writer, or Impress by selecting the appropriate import filter. Here is the rub–at that point you are no longer working with the original PDF–it is by the side as a locked file. You are editing a new ODF document. When you finish editing that ODF document you can save it, or you can filter Export it to a new PDF. Point is the content of the original PDF has been filtered on import to LO, and then again on export and you are asking for heartache to think of LO’s handling as “editing” a PDF. PDF are not structured to be editable! .