In Yoga philosophy, which I practice, you are an immortal soul, the spark that gives life to or drives the physical temple. This in turn is part and parcel of a Higher Entity which some call by various names. Let us call it the Absolute Supreme. You are NOT the body, but the Soul!
In accordance with cosmic law, the physical will grow old and decay or die, but the Soul cannot die. Actually, death occurs while we are alive and not conscious of our Source and also while we are conscious of our Source also, for the mystic can visit the inner ream at will.
Reincarnation is the process whereby the soul involutes (comes down) and evolutes (evolves) from the mineral to the vegetable to the animal to man (which is initially still animalistic) and finally to the divine. It is like a wheel, whereby we take a new form from birth to birth, each generally higher than the other in terms of growth of Consciousness, until we finally come of this wheel. This is motivated by desire, which is a necessary drive.
God-realisation or Self-realisation, is the state whereby the individual soul merges into the Supreme Soul and becomes inseparably and consciously one. Any incarnation after this is generally for the purpose of serving mankind, or if you like, reminding us of our true nature, which is Spirit or God.
Yoga is also Spirituality and the true God-seeker does not separate. He or she knows that all are important: religion, politics, science, adversity ... all is a part of this one indivisible WHOLE. There are no boxes. Hari Om!
P.S. Asking should come from yearning; an inner cry; a longing to know. Without this, question can sometimes come from the mind, full of suspicion and separation; a willingness to divide or analyse ... in this sense, it restricts growth. Hope that yours come from longing. the quality of the child. Much Love.