Sam Harris’ book Free Will is the most clear and cogent piece of writing on the subject of free will that I have come across.
If we follow the assumption that our mind states, our thoughts and feelings, are the product of the neurochemistry of our brain, then we must agree that as none of us have sculpted our brains, we are not in control of our minds.
Even if we believe that we have souls, then the same argument applies. We did not create our souls, therefore we are not “responsible” for them.
These summaries above are crude approximations to the elegance and power of the book, which I urge you to read now. Especially in the light of non-dual traditions, it makes for powerful reading.