What Do i have to do or replace?
 

I was installing a new key ignition switch in my 95 civic hatch, i dont know what happened exactly but it made a big shock on the back of the key piece of the harness where its soldered, after that it would only turn on alll lights before you start the car but when i try to turn it over it doesnt work.... what do i do....

Check the fuses, including the main fuse in the engine compartment.

You shorted out the switch. Get a new one. This time, remove the ground from the battery before you install it. Do that every time you replace something electrical.

check for a soldering bridge, this is when the solder connects the two terminals and shorts out the system. and a fuse should blow out before any electrical equipment gets fried, so definitely check the fuses, probably one in the main distribution box under the hood, not udner the dashGood Luck