The easiest newbie way to do it is to mount the wheel on bearings on a "dead" axle that is just a bolt thru the frame. The sprocket then bolts to the wheel.
Whether or not you need blocks to mount the dead axle, depends on the design of your frame. The kit frame has flanges with holes in them designed for a bolt type dead axle. If you use that extruded stuff then you may need to make blocks or angled plates to mount the axle.
With a live axle, connecting the sprocket you can buy hubs, most teams who use a live axle make most of the parts themselves, it's not really a newbie appropriate thing to try unless you have good help.
here are some of the hubs, the keyed and hex hole type are what you might use
http://andymark.biz/hubs.html