you want to learn magic? by your wording, i'll assume you want phenomenal cosmic powers [ just how you worded the question] first, you need to learn what is magic, then start out with meditation, increasing energy and grounding before you can start out with magic. basics first.
magic is energy anyone can do magic, and you don't need to belong to a pagan religion to preform magic. start with meditation, clear your mind, try focusing on one thought, or your breathing. then imagine a ball of light, or a waterfall, or whatever. [well go with a waterfall for now] as you sit under the waterfall, visualize the water washing over you, the pure water takes all negative energy downstream. once you feel ready, you need to build energy.
building energy can be done in many different way, i use focus, some people chant, others dance, do something that builds up your energy and makes you feel excited/energized/hyper/full of energy. ground also can be done in a meria of ways, some people just visualize, myself, i tap the gound with my athame, some slap the ground, lies down, falls down, my friend stomps his foot. whatever way feels right for you, release the energy you built up into the ground, so you feel tired/drained/sleepy/drowsy/weak.
once you've got a good candle on these things, you can begin casting. start with candle magic, since it's [to me at least] the easiest. we'll use luck for a basic spell. get a light green candle, carve your name in the base and a clover/horse shoe or anything you feel is lucky into the top. if you wish to carve the name of a diety associated with luck in the middle of the candle you may as well. rub extra virgin olive oil [for starting out, it works, i'd use oil for luck, but for a starter spell, it works just fine] rub it in circles from the base to the top, then again from the base to the bottom. you may say a chant if you would like, then light the candle and let it burn down visualizing what the luck will do for you. if you don't want to burn it down completely, snuff out the candle with your finders, don't blow it out you will blow away the spell. [though some people feel you are sending your spell into the universe, but myself, snuff it out] .
i know that was long and winded, but i hope it helped a little.