That's not good
Hate to be the barer of bad news but when the key spins the belts, the crankshaft is turning over. If you had listed the year make and model of the car it could be something as simple as a fuel filter low fuel pressure or no fuel pressure.
List year, make, model of car. Include if there were any symptoms you know about before complete failure.
If it is not turning over, then the starter is not turning the engine. If it is not catching but the starter is turning the engine, that is a different problem.
Cats are tough. If completely blocking the exhaust then the car will not start. However, the starter should still be turning the engine.
My daughters car completely died, the best way to describe what it's doing is........ turn the key it turns the belts but will not turn over and then a psssssh sound from what sounds like coming from the bottom. I don't want to drop a new engine if not completely necessary..... HELP!!!!
