Drop Down Menus for Newbie

I need help. A friend helped me get my website up, www.alimeghdadi.com. I need to figure out how to make drop down menus for the pages of my work. How does one do this?

I don't know a thing about computers. I'm doing my best to figure this out. I've downloaded lots of plugins, however none of them seem to have exact instructions for newbies.