The engine cranks but does not start?

So, I came home from work car ran fine parked it got into to leave, and it wouldn’t start. It would crank but not start. So, I noticed the fuel gauge had been acting up which in my case usually means my fuel pump was about done. So changed out the 24-year-old fuel pump and replaced the battery. Still same thing. So finally noticed when trying to start the car the security light would start flashing. So tried to relearn keys and FOBs. No such luck can’t get car to go into programming mode. Also, I noticed the RIM (rear integrated module) module had got knocked down. The retaining clips had gotten broken so I’m thinking that this might be the culprit. I noticed there is a metal tension spring on the back. Went ahead and placed it back up in its spot. Still same thing cranks no start no spark.