I'm nearly through refreshing knowledge on anatomy. Theories on what to imitate. -55mV membrane potential of sodium and potassium ion channel exchanges for a sense of touch. Synovial joints such as pivot, saddle, ball & socket, condylar, hinge, plane and fibrous. Neurons, beta receptors, optic nerve cones for sight. Muscle actions, myosin and actin. Taste receptor epithelial cells, auditory ossicles for hearing etc.

Next may be prosthetics. If failing to understand that, probably electrical engineering and mechanics first. The body must be crafted before the hard drive brain and Operating System so I'll know what to connect it to.