You have to have a water supply from somewhere. It's only a 1/4" line, much like a refrigerator's icemaker uses. But more of a problem is that you also need a drain line for the waste water. Of all the water that goes into the filter, only about 25% comes out the filtered line. The rest goes to the waste side and needs to be disposed of somehow.
Bottom line, you'll need some plumbing installed - a water source and a drain.