I always say the same thing, no questions are stupid, after all, none of us were born knowing all of this .
As far as power requirements for your plane, if you can approximate the AUW, or flying weight, you can figure your power system pretty easily. Let's say for instance that the AUW will be 15 lbs. For decent power and scale type flight, I would aim for around 125 watts/lb, so that would be between 1800- 1900 watts. Since your plane is a twin, you should shoot for around 900-950 watts per motor.
You will then need to find out what diameter props will fit the plane. Once you know that info, you can then figure what Kv rating you will need and what voltage you will want to run.

I will give you an example:
I just finished building an E-flite Deuces Wild. It's a twin also, and the AUW is just North of 10 lbs. It's a sport plane, so I knew I wanted 1200-1400 watts for decent performance. The manufacturer states that a 13" prop will fit, but the ground clearance is much better with 12" props. The motors are counter-rotating, so I needed to see what pusher props were available in that size. I decided to run 12X6E props, so I'm running 2 650Kv motors on 5S, or 18.5 volts. I could have run 12X8E props and used 4S packs, but the higher voltage requires less current, which in turn, gives me better flight times, and the equipment stays cooler.

Hopefully this will help you with your setup, keep us posted and good luck.