How Do I Separate Staffs?

Hello,
Wow, I got a lot of great feedback from some super nice subscribers. Thank you for helping learn how to add an extra staffs to my music. I have one more questions. I added a second and third staff to my piano piece, but now I have another dilemma the staffs are all connected together and when I push the play button to hear what I created it plays all the notes on all the staffs at the same time. Can someone tell me how I separate the staffs?

I'm sorry if this is a silly question. I'm still trying to master this program. Thank you so much for all of the help and advice.
Fawn :-)