Starter whirring, engine not starting?

I totaled my car, but I replaced everything that was broken. Radiator, A/C, upper and lower intake, and the starter. The starter wasn’t completely broken, but the housing where the solenoid is was cracked so it was loosely hanging off of the starter. I had the alternator, starter, and battery checked and they’re all good. The flex plate teeth looked fine, but when I tried to turn the engine manually, it turned way too easily just by using a socket on the crankshaft. The engine started once then stalled out a few seconds later. Now it won’t start but you can hear the starter whirring. Fuel pump is priming, spark plugs are fine, but engine will not crank. I can just hear the starter spinning.