How to open or use WPDEV themes

I am totally new to WP.
I believe I have downloaded Dashboard, but how do i get that to open etc.
I can see the php files.
Just downloaded 133 Farm themes.
How do I open it?
How do I actually see anything? A zip file, how do i get it to open, start etc.
As I said totally NEW and inexperienced in WP.....
HELP!!!!!!