Send a fax from your Mac
Make sure you have a telephone cable connecting your Mac to a working phone outlet. (This assumes you have a modem built in to your Mac, which you do unless your Mac is really old.)
Open the document you want to fax.
From the File menu, choose “Print….”
In the standard Apple dialog box, click the “pdf” button in the bottom-left corner and choose “Fax PDF… .” If you're using an application that has its own print dialog box, such as Adobe InDesign, you'll usually find a button at the bottom of the dialog box that says something like “Printer….” Click that button, and there you should find the “PDF” button.