CONNECTIONS PROBLEMS.HELP

I Got My Midi Connection From My Keyboard 2 My Mpc 1000,my Question Is Do I Use My Other Midi Connection To Connect To The Interface Or Do I Use My Other Line In Connections 2 Connect To My Interface?IM TRYING TO USE ALL THIS WITH CUBASE AND REASON

I may be wrong so anyone feel free to correct me.

1.Keyboard midi out to mpc midi in.
2. MPC out to interface in
3. MPC stereo out/Assignable mix out to line in's of interface

Think that is how it is done.

3. MPC stereo out/Assignable mix out to line in's of interface

SO DOES THAT MEAN I HAVE 2 HAVE 2 PAIRS OF CABLES EACH FOR
STEREO OUT TO CONNECT TO LINE IN'S OF INTERFACE AND.....
ASSIGNABLE MIX OUT TO LINE IN'S OF INTERFACE?

THX 4 HELPING OUT MAN