Might need more info to help, but shooting from the hip; playback (in fact, all Audio going in OR out) gets passed thru whichever interface you set, according to the IO setup. You listed a 96 IO and a 192D. The 192D has ONLY digital ins and outs so its going to need A>D and D>A to be of any use(more on this below). So for now, let's assume the 96 IO is your main interface. You need to go into the IO setup and set outputs 1&2 as your main outputs. Those 2 line outs(TRS jacks) get sent thru a monitor controller(assuming the Pro Control offers this function?) and then to your speakers(assuming powered studio monitors). Read the manual on the Pro Control to see if it offers monitor control for the above setup(if it doesn't, then grab a monitor/source controller like Presonus Central Station, Mackie Big Knob or similar).
Back to the 192D. To get use from this box, you need a way to feed audio to it(A>D) and optionally, return audio from it(D>A). If 44.1 and 48K are sample rates you will work at, then lightpipe can be used and you can get started on a fairly low budget. Behringer ADA8200(the red unit) has 8 mic preamps(decent Midas design) plus 8 outputs with lightpipe(aka ADAT) connections. Focusrite OctoPre Dynamic is another option for both ins AND outs. (IMHO, the focusrite is no better, but does cost way more). If you want MUCH BETTER preamps, the Midas XL-48 is a great 8-channel preamp that can feed into the 192D via lightpipe or AES. What it doesn't have is the 8 outputs(only you know if you need that or not). In any case, clocking needs to be done correctly and the 96 IO and 192 IO need to have Loop sync connections(not sure how the SYNC IO factors in so other folks may offer additional direction)
Given how little experience you have with this stuff, it might be worth paying a local "expert" to come help you get everything configured