Okay, it sounds like the flywheel may be broken at the back of the motor where the starter engages to turn the engine.
The transmission has to be removed to gain access to the flywheel. I attached the procedure below for you.
https://www.2carpros.com/articles/how-to-remove-an-automatic-transmission-rwd
Make sure you replace the bolts that attach the flywheel to the crank. They are TTY or toque to yield. That means you use them once and throw them away.
Roy
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Sunday, January 16th, 2022 AT 6:49 PM