well, Im in the same boat as you.
My advice would be to learn all the major scales and the numbers that correspond first. Learn them all real good like the back of your hand. Thats how you learn to play in every key.
From there, learn all your chords in every key. after you at least get the gist of major and minor chords, start learning progressions. Listen to gospel songs and try to identify progressions.
Thats how you at least get started.
I would suggest you get Gospel keys 101 if you are a beginner. it will explain all the basics.
In my opinion, there are two keys to learning gospel music.....
1. Learn the theory
2. Learn where to apply the theory in gospel music.