One of the major revelations to Windows users when they migrate to Linux is that its no longer necessary to pay for a PDF printer, or install an open source one: Linux knows how to print PDFs already. However its default implementation is a little irritating. When you print you have to accept the document name and location that’s already there, or click through a few dialog boxes to change it.
But there’s a CUPS package that can improve on this. On Ubuntu/Debian varieties, type
sudo apt install printer-driver-cups-pdf
On other distributions look for something similar.
Now when you print, select that printer and all your documents will be saved in ~/PDF/ with a descriptive filename based on the window title.