I'm looking into getting into theatre next year?

So,today my brother gave me a brochure for a Memphis Theatre,and there doing a production of a movie that one of my favorite directors (Bob fosse) made;Cabaret so i finally started to work on being a stage actress but i wanna educate myself before i go on stage and make a jackass of myself,so i would like to know how i can practice dancing and exercise my voice,since i notice the oddest thing i can only sing (well) when it rains? I guess because it's soothing,but i just want to work on my singing voice,but i haven't the slightest idea on where to start,please help?