See a PDF in Safari on Mac
Safari has a built-in PDF reader that automatically displays PDF documents right in the browser window. You don’t have to download and install a separate PDF reader app.
See a PDF in Safari: When you see a link for a PDF on a webpage, simply click the link. To stop viewing the PDF, click the Back button in the toolbar.
Zoom in or out, save the PDF, or open it in Preview: Move the pointer to the bottom center of the PDF page to see controls for zooming in and out, opening the PDF document with Preview, or saving the PDF document on your Mac.