If your will—what you want—is determined by what you have learned through your environmental, parental, and sociocultural conditioning in conjunction with mimetic processes, then how is individuality possible?
For one thing, all the learned contents, coming from an innumerable amount of different sources, are intermingled in a way that is perfectly unique to you: it is your personal learning history, which, in addition, is not linearly imposed onto you, but dynamically shaped by how you react to certain types of conditioning. For another thing, this potpourri of influences on your will is integrated within your brain in deep interaction with your genetic code, which is also unique to you (unless you are a monozygotic twin). Thus, the end product that you experience as your will is individualistic in the sense that nobody else on this planet has the exact same will as you.
We can also draw a parallel here to the question of creativity: If your mind—what you think—is determined by what you have learned though all the sensory information that has ever left a mark on your central nervous system, then how is creativity possible?
Again, the answer lies in the way the incoming information is idiosyncratically mixed and integrated in your very own head. However, if your creative outputs are too closely related to a discernible counterpart already existing in the world (for example, if your artistic style is just a cheap copy of well-known legend), then you won’t be seen as creative, but discounted as unoriginal. This is not to say that in order to be original you would have to be some principal point of origin (perhaps a receiver of divine inspiration?), which is a metaphysical misconception; instead, it is to say that the origin of your ideas be indirect, varied, muddled, and irreducible enough so as to count as creative.
The same holds true for your individual will: A direct line that can be drawn from your action to an obvious external trigger (for example, you got brainwashed, peer-pressured, or seduced into doing something) provides a clear, reducible explanation for why your will does not count as individualistic. By contrast, if no one can find any direct causal connection to any specific conditioning event, then your actions will exude the scent of individualism. Importantly, your individuality goes no deeper than that: its essence is nothing esoteric, but the mere limitation of man’s ability to detect nexuses.
To conclude, there is no such thing as pure individuality or pure creativity, because both are deeply rooted in the impressions produced by your environment and community (in the broadest sense of the word). But the more extensive and complex those roots are, that is, the more obscure and indirect the links between your learning inputs and behavior outputs, the more individualistic and creative you may feel about your will and mind, respectively. Certainly, this is how you can expect to be judged by others.