not 100% sure what you mean. a thought form is an option, as mentioned above, possibly astral projection, or incorporating their energy into certain spells, yes. if you're asking for a spell to make you into a phoenix then no, i'm afraid there is none.
to repeat what's been said a thousand times or more, real spiritual magick is energy found in nature, focused by the caster in a direction, and used to achieve a goal such as luck, love, or protection. this energy is a force of nature, therefore it cannot go against nature. if you wish to cast a spell that a normal human cannot do [fly, teleport, shape-shift] then it cannot be done by magick.