Premiere

IF/When you do have a download, be sure to copy it to AT LEAST one external device
-since Adobe does sometimes remove old versions from the server
-a usb flash drive or hard drive, or write to a DVD

(you'll need to follow the directions esp, step 1 if you use prodesigntools.com links.)

Hi

You can download CC 2019 from here, which is compatible with your version of MAC OS

https://prodesigntools.com/adobe-cc-2019-direct-download-links.html

you can install the latest and 1 version prior versions using the cc desktop app. you must have a subscription because previous versions are not available with trials.

other versions are revealed in the apps tab by clicking the 3 dots adjacent to the open/install button after clicking file preferences>apps>tick show older apps (at panel bottom).