For example, I predict that in a few minutes I will turn off the computer and go home, buying groceries at the supermarket on the way

And that is exactly what I did. And for my next trick, I ate because I was hungry, and tonight I will sleep when I am tired.

The sensation of free will is the experience that our acts seem to us to come out of nowhere. But they do come out of somewhere; a part of us that is inaccessible to experience. The sensation is real, but to interpret it at face value is like imagining that your head has no back because you cannot see it.