If you could not find the zip installation file then this happen because of safari auto extracting comppressed files

to solve this issue..

In the menu bar, go Safari -> Preferences. In the "General" tab, uncheck "Open 'safe' files after downloading". This will stop Safari from automatically unzipping the files.

also This post will help you https://www.wp-buy.com/how-to-install-our-plugins/

thank you