Need help. Battery light on.
 

I have a 1995 honda civic ex with a swapped turbo b18b1 engine. I am having a lot of trouble starting it. The battery is in the back and when I go to start the car the ding sound starts to tell me the key is in, I go to turn on my electrics and they work, and then I go to start the car and everything goes black. When I turn it back the electrics do not work and it doesn't even make the dinging sound anymore. When this happeneds I have to go back and reposition the positive pole on the battery, then I repeat the process. The battery is charged and full and is new, it is 1000ca so plenty big enough for my engine. What could this be? Also the battery light comes on when the electrics are on. Thank you for any help you can give.

Battery light should be on when the key is on with engine not running. It should then go out after starting.

Take the terminal completely off of the battery, clean the battery post and the inside surface of the terminal down to bare metal. Then loosen the nut enough so the terminal goes all the way down to the top of the battery. There should be some of the battery post showing above the top of the terminal. Finally, tighten the nut. Do the same thing on the negative side. (For safety, you should disconnect the negative terminal first and leave it off while working on the positive.)

On also when I try and jump start the car with jumper cables. The car does not start. What could it be?

"I have to go back and reposition the positive pole on the battery..."

You've already found the problem. Fix it like I said.