I'm not sure this is described well, but suppose I use the shape tool and create a square with a fill of Black. Now I take the text tool and create the word "test" in the square, then convert it to vector by doing type>create outline. At this point I have my canvas->black square>black text. I want to change the fill of the text to none, and have the white canvas show through, as if the text is now transparent.
I'm using Illustrator CC.