A orange light on the dash (car with key flashes and wont start)
what and how do i replace the broken part ?

 

That signigyes a problem with your immobilizer. It doenst allow the car to run if an invalid key is used. It will just start run and die. Try another key. If another key starts the car and everything is ok. You have a bad key. Otherwise you probably have a problem with the reader coil in the mechanical part of the igntion switch. It could also be a instrument cluster or ecm problem.