My flywheel is turning very easy by hand

Is the flywheel still attached?

Does the engine still turn over on the starter motor? Maybe you have broken a crank shaft, if the flywheel turns freely, try turning the engine from the front pulley and see if the flywheel turns.

You have not answered my last question, if you turn the engine by hand at the front pulley does the fly wheel turn? Now, you say flywheel. So it is a manual. Otherwise it will be a drive plate with a torque converter attached, so with that said, are you looking at a torque converter spinning independently of the drive plate or a flywheel spinning free of the crank shaft, we rely on your eyes to see what is going on, so accuracy is important.

Have the starter tested, check that the teeth on the drive plate are not damaged in any way, next is a bit tricky, set a pencil up so it is just touching the drive plate through the starter access, turn the engine and watch if there is any major deflection on the drive plate, use the pencil as a pointer or a scribe line if you can get a good section that will scribe up as you turn the engine.

I would say possibly a cracked drive plate or loose bolts for the drive plate or torque converter, time to pull the box I feel.

Yes.