The atty comes with a blank cart that does not have any fill in it. It can be used if you put some fill in it.
The liquid you are seeing is put in there at the factory to keep corrosion away. (If we are talking about liquid in the atty bag.) You will need to get that out. Blowing from the
threaded end, with the cart off, a few times will get most of it out. Without any extra
juice, you cannot prime it. So you will want to rinse it out and blow it out again. This should get rid of most of the fluid so that the prefilled carts that probably came with your kit will be usable.
Note that the prefilled carts always tasted nasty to me, no matter what they were filled with. Some don't mind them and some prefer them. Taste is very subjective.
I also highly recommend reading
http://www.e-cigarette-forum.com/fo...ping-illustrated-guide-e-cigs-part-1-6-a.html to give you an overview of the world you are getting ready to step into. I found it best with a fresh battery and a full cart.