Novice - the first things to look at are the nut and the fretboard at the 5th fret. Many British made 5-string banjos were made using machine heads manufactured for guitars. Only five of the heads were actually attached to a string.
Four of the strings went over the full length of the fretboard, so on the nut, you will only find four slots for strings. The fifth string disappears down a brass tube which is set below the fingerboard. The tube (and string) then emerge near the 5th fret (usually to go over a small individual "nut") in the position where, on a standard 5-string, there would be a tuning peg sticking out of the side of the neck. From this point, there are five strings going down the neck to the bridge, and then to the five attachment points for the loop end of the strings.
If my description matches - you have a 5-string "zither" banjo, which can be played using any style of playing that a standard side-peg banjo. There are plenty of discussions on mudcat about styles and techniques.
If not - ask more questions here.
Quack!
Geoff the Duck.