How do I connect a car stereo setup in my room?

[AnthonyG1]

I'm new and still learning about speakers.

How do I connect , an 800W Sony AMP, 2 12' Kicker COMP, 8Guage Wiring, to my room?

I'm aware of using a PSU for computers. But is there a similar way. Like DC to AC convertor?
If I buy 2 PSU can I connect both into the one amp to get more power into the amp?

I have the music source already.[Substitute for headunit]

Please be very specific!