This is a subject which tends to make a lot of people angry when you mention it. Because one of the cherished human illusions is that we can exercise choice. That we have free will.
There are a number of reasons why this isn't in fact so.
1. Firstly. we don't choose to be the person we are. This is influenced by our genetic make-up, our parenting, our social experiences, the self-image (or ego) we perform to and - most importantly - what we are passionate about. But we don't choose our desires - Bodymind does. Yet our emotions dictate what we pay attention to before we come up with reasons why we do the things we do.
2. Many of the things we think we have voluntary control over are actually performed automatically. This applies to doing sums in our heads, driving a car, or making decisions about which job to take. Our selections are based on elaborate rules we carry around in our heads which we learned from others. Going through the rule flowchart results in what we later on call 'a choice'.
3. We can't make choices where no choice is available. You didn't choose your parents, the nation you were born in, or the justice system. Nor did you have any real say on the way your school, your job, or the banking system works. Unless you have the right physique you can't choose to be a champion athlete; if you don't have a gift you won't be an artist; if you are blind you won't be able to distinguish visual objects.
4. Many of the choices we think we make are actually influenced by other people. That could be your partner, your boss or your children. The majority of the world's population live in societies dominated by authoritarian regimes, the military, political and tribal cliques, or by the media.
5. For the most part we don't create our thoughts. Instead our thoughts happen to us. They come unbidden as we turn our attention to the things that catch our attention. This is clearly shown in those '"eureka" moments when we realise the solution to a problem.
6. The same applies to much of our physical behavior. We don't choose to smile (unless we are acting). Nor do we choose how to digest food, walk along the ground, sleep, wave 'hello', cry, laugh, react to a sudden noise, or create an emotion.
7. Brain research shows clearly that decisions are made by Bodymind, in the Brain, before we are consciously aware of what it is 'we' have decided. For the most part conscious mind merely comes up with reasons why we have acted in the way we did - after the event. You can see this feature at work in many criminal trials in which people come up with excuses for the way they behaved.
8. Hypnosis shows how easy it is to make suggestions to people to behave in a certain way which they then perform automatically. After they have awoken from trance they are either unable to explain why they acted in that way or they make up trivial reasons why they did so (although this is, really, an exaggerated example of what many people do in everyday life in any case).
At the very most, all we can claim is that we have the power of (sometimes) selecting alternative means of achieving the desired goal - goals which are in fact determined by the kind of person you are, your passions, your experiences and the things you have learned.
I would argue that you only really have one choice (which does not involve free will).
You can choose to be true to yourself or not - your personal genius, your authentic, lived, experiences, the values you have acquired and your loyalties. You can also choose the friends, teachers and guides who can help you become the person you were born to be.
It's just that you can't choose your personal genius - your 'soul' if you will. It chooses you.
'My formula for greatness in a human being is love of one's own fate, that one wants nothing to be different...'
Nietzsche.