I don't know anything about Mac, but with Windows you right click and select "Open With", but, you have to have a Zip program on the computer to open it with. I would guess that Mac has something similar to "Open With", but, you will still need a Zip program.
I'm certainly not too knowledgeable about such things, but I googled how to unzip on a mac and the apple support said just double click on the file. I did that and nothing happened. I'll keep looking.