[@UltraCraftGames]

Gods - Yes, they exist - however, they're forgotten. Reason> Gods were abusive dicks, Mortals curb stomped them 
Planes - Sort of, but nothing a mortal could ever see into. They can know, just never witness it

As for how Maa'jhick/Magic works, basically like a muscle. The more you train, and the more you learn for the training, the more powerful you become.