A stupid question ?

Ok __ I don`t think any question is stupid , I just don`t have a lot of MIDI experience , so here goes !

Can you use the BK7m like this :

Somehow ( don`t know how ) hook it up to a digital piano and turn it into an Arranger ?

Always played live , never bothered with midi. Years ago I tried hooking up a Yammy X4500 to a PC using the really old Roland MIDI box + MIDI card , but never had much luck with it.
Not sure if it was me or the fact that the X-4500 only had 8 note poly

Anyway , thanks for your help

Gary