What does revving yor car do?

My dad has an old 2014 Honda Civic and he just recently got me a new 2016 Honda Civic. Today I saw my dad opening my car's hook and his car's hook. He attached some kind of wire I think to both of the cars and then he went inside my car and revving it. What exactly was he doing?

My car has been taking a little bit longer to start

I bought a Honda Civic from car max a few months ago and when I turn the key it starts after a second but when I haven't drove it all day it'll take a few more seconds to start. Like it use to be just "jujuju" but now it like 7 or 8. I don't know anything about cars but I was to fix the problem now before it gets worse.

2003 Honda acceleration issue

I'm thinking of buying a 2003 Civic. It takes a moment after I hit the gas to start accelerating. Once it's going, it's fine. What might it be? Not a Honda guy, but I can fix it once I know where to start.

Has had the plugs replaced not too long ago. The vehicle has 125k on it, but has been maintained pretty well. Any help would be appreciated.

Drove Honda civic 2001 without coolant for a few minutes. Potential damages?

I was driving about an hour with the ac and noticed a rise in the thermostat but it went back down a few times. At one point it got to the danger zone but went down quickly. There I knew there was a problem. Again it went to the danger zone so I decided to stop but I waited for an exit; I would say I drove 1 maybe 1.5 miles before I took the exit on the freeway. The car had burned through the coolant and was making a bad noise where the reserve coolant tank is and shaking it slightly. I filled it with water and drove back, which was about 95 miles to get home and it went fine. I'm gonna get it checked before replacing with 50/50 coolant.

I'm worried that extra driving caused something serious. Yes I'm an idiot for not stopping immediately, I'm a young driver. Again, the car drove perfectly fine after filling with water for 95 miles.

Can I use 50/50 prediluted green antifreeze on Honda Civic 2001?

Can I use 50/50 prediluted green antifreeze on Honda Civic 2001? - 1

Added (1). I bought antifreeze at a gas station in a hurry without reading the label. It mentioned that it worked best for certain models but did not mention Hondas at all. Is it okay to use in my car?