The title explains 99% of my question.

My first kit is the prusa i3 x and when i master single extruding I wish to move on to dual extruding.

the prusa i3 x uses a single mk8 extruder, but they sell the mk8 dual extruder - however, I don't imagine it's as simple as attaching it?

is additional software or hardware needed?

sorry if this is a newb question, I am a newb after all