A bow is the main weapon of a ranger. It takes both hands, so it can't be combined in any way.
Very useful for ranged attacks. With it you can defeat enemies (those who don't have ranged attacks or those are easily avoidable) in a safe way.
The first bow you get on Ego Draconis is Avair's first bow which you obtain after talking to Morgana, then heading to Avairs, and selecting 'ranger', as your skill path.