2006 chevy silverado

2006 Chevy Silverado
What are possible reasons as to why my truck would stop running while driving? It did not make any sounds and no warning signals it just slowed down and powered off, and would not start. We checked the alternator and replaced the starter. The truck started but was running really rough with a lot of racket and then just died and again won’t start it just clicks when you turn the key and doesn’t even attempt to fire. Please Help!