A non-computer question from the lady who didn't know what an AC Adapter was... [View all]

I'm hoping to learn how to make music by recording and layering on, either myself with myself, or myself with my trio buddies. I'm getting good info about mics, but I also would like to play my recordings on my good speakers, currently hooked up to the TV and cable box. But it's a nightmare. In the picture below, the red and white connections at the bottom go to the cable box, and the ones on the right go to the TV. I've hooked up a tiny speaker to my computer, so I know it doesn't us a double wire (although, interestingly, there seem to be 3 little holes to plug the speaker in, and it doesn't seem to matter which I use.

Is it possible to hook my computer up to my receiver that's connected to the good speakers?

If yes, what kind of wire would I need (specific name for searching Amazon and eBay, please)

Where would I plug the wire into the receiver?

Does it matter that the recording is made on the computer, assuming I use a good external mic?

Thanks much in advance,
LAS