It depends on what you want them to work for. You aren't going to teleport your physical body. But you can teleport your soul. You aren't going to levitate your physical body. But you can levitate your soul out of your body through meditation and astral projection.
Well, it really depends. First off, levitation is a practice of its own, and like magick, not scientifically proven to 100% work all of the time. The practice of levitation takes much energy and concentration. Most people believe it to be un-accomplishable, but remember, nothing is impossible. For teleportation spells, it is highly unlikely to be able to transport your physical body, but you can travel with your spirit, hence astral travel or projection. Also, you can travel into different realms and levels of consciousness through meditation and trance. Do remember - nothing is impossible.