Yes it will grow if the kernels are undamaged. Mice haven't chewed on them? Maybe not 100% of the kernels will grow, maybe 75% or so will. Shell it carefully by hand.

Yes, they will grow into "indian corn" again.

When we were still picking ear corn & cribbing it, we would put a handful of indian corn kernels in the planter boxes every time we filled the planter w/seedcorn. Then in the fall when unloading the wagons into the cribs, it was quite a treat to break the monotony & pull a nice big colored indian corn ear out of the wagon load of yellow corn.

I don't think a puple kernel will necessarily grow another purple ear, you'll get an ear w/mixed colors again.

Good luck with the indian corn.