...what a soul is and whether I have one?
The human personality is identified with mind and spirit held together in functional relationship by life in a material body. This functioning relationship of such mind and spirit does not result in some combination of the qualities or attributes of mind and spirit but rather in an entirely new, original, and unique universe value of potentially eternal endurance, the soul.
Material mind is the arena in which human personalities live, are self-conscious, make decisions, choose God or forsake him, eternalize or destroy themselves. Mortal mind is a temporary intellect system loaned to human beings for use during a material lifetime, and as they use this mind, they are either accepting or rejecting the potential of eternal existence. Mind is about all you have of universe reality that is subject to your will, and the soul — the morontia self — will faithfully portray the harvest of the temporal decisions which the mortal self is making. Material evolution has provided you a life machine, your body; the Father himself has endowed you with the purest spirit reality known in the universe, your Thought Adjuster. But into your hands, subject to your own decisions, has been given mind, and it is by mind that you live or die. It is within this mind and with this mind that you make those moral decisions which enable you to achieve Adjusterlikeness, and that is Godlikeness.