Looking for a free version of acrobat.
Ciao, Libre can directly convert a file to .pdf. Libre’s Draw can open certain .pdf files to edit and save them.
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if you are creating PDFs from a .odt file, after creating the PDF, it is a good idea to also save and keep the .odt file and use it any time you want to edit the PDF. It’s much easier to edit a .odt than a .pdf in LibreOffice.
Even easier is to click on File in Writer, click on Export as PDF, then, under the General tab, put a check in the box for Hybrid PDF. This will set Writer to embed an ODF file in the PDF when you export to PDF. That way, when you want to edit the PDF, just open the PDF in Writer and the ODF file will automatically come up and you can edit away, then resave it.