Every time you post we get more info, now it is a key assembly whatever that is. Without the key chip programmed to fit your car nothing will run for more than a few seconds, you can program the fob to open the doors but you cannot program the chip inside the fob to run the car.
The key may fit the doors and ignition.
The chip may or may not be the one to start your car, someone may have purchased a key on eBay it may work the doors but it will not get the car running for more than a few seconds, maybe less and maybe no starter action at all.