That's right, magic is something innate. You can be taught to hone your gift, but if you do not possess that spark to begin with, all the lessons given will accomplish nothing.

Magic can do many things; heal wounds, energize debris to create walkways or repair structures, provide a protective barrier, damage ones enemies with ice or fire or lightning...and so on. I don't mind giving a demonstration for those interested. Knowledge is key toward fighting the present bias against mages.