New mopar owner…hi!

I have recently lost my father, a mopar enthusiast. He left me one of his cars, my favorite from the bunch. A 1966 dodge charger. I have always loved this car, since I first rode in it at a very young age. Now I need to learn more about it so I can speak intelligently. In the interim, would anyone be able to help me with a concern? The car is being stored for the winter in its usual spot, an old barn with one stone wall side. We have gotten a few feet of snow and now that its melting, in conjunction with the recent rain, water is coming in and pooling under the car. This can't be good for it and I don't know how to fix it just yet. I vaguely remember my dad getting a full undercarriage sprayed (I hope that's the correct terminology). Is there a way to tell if this car was done? And do I need to act fast or can I wait til spring to fix the stone wall leak? I don't want to let anything damage or jeapordize the currently solid body.
Author: Souprmom