Lots of little questions!

I got a rolling wrench gy6 skinny wheel swap kit and did everything in the tutorial video and I got some questions before I turn it on for the first time.

Pic 1 - what is this box on the end of this tube that connects to the front of my gy6, is it needed, is it a replacement for the box that’s connected to the black metal piece on the frame?

Pic 2 - The new cable from my rolling wrench gy6 swap kit doesn’t connect to the stock cable. It only has one prong, could I pull the one prong out, connect it to the stock plug and tape it up?

Pic 3 and 4 - This tube I was told to dis connect from its back half that connects into the gy6 and tuck it into the filter. This just seems funky and leaves the pic 4 tube hanging loose and odd what should I do?

Pic 5 - the stock engine had coolant and such but the gy6 doesn’t. Is that normal and do I need to get coolant connected up somehow? It’s not spoken about in the tutorial RW video

Pic 6 - this ground cable wasn’t in to tutorial video and wasn’t used from the kit which seems odd what should I do with it?

Pic 7 and 8 - how do I go about draining my old gas before I pump it into the new gy6 and this frame piece fell off today and idk where it goes

THANK YOU FOR THE HELP!!!