Recently purchased a 1998 Audi A4 Quattro 2.8 auto anyways long story short cranks up fine idles fine car shuts off when put into any gear unless I crank it in neutral and kick into tip mode it. We had a bad flood here in SC and battery compartment was flooded also 99% sure tcm is submerged in water. Any help/advice would be greatly appreciated.

The battery compartment? You mean up to the base of the windshield? Hard to believe that it even starts!

Sorry should of specified more clearly not up to the battery compartment but the rain drain under the battery was clogged. Anyways added engine oil it was low and now it goes into gear but won't move? Took the tcm out it was drenched this car is a mess starting to think I got myself into a little more than I can handle. But for 300 I couldn't pass it up.

So it shifts into gear fine but when you press the pedal it just revs? Sounds like you need transmission fluid. Were I you, given the circumstances, I would drop the transmission pan, clean that out, get a new filter and gasket, put it back on, then add fluid. To make sure it is fluid, you can add it now to see if it works but you'll likely have to throw all that out when you replace the gasket/filter and it's a little expensive to do twice in a short period.

Yeah waiting on my new tcm to get here, a faulty tcm wouldn't cause those symptoms though right?

maybe? it sure sounds like it could but i have 0 experience - I have a stick.