What I think about free will (EN free translation)

I think we are machines, just like a virus or a bacteria is a machine build with molecules. This machine is built according to a program (our DNA), which is more or less well executed during pregnancy and our first years. The way the program unfolds varies slightly depending on the physical / chemical / biological environment in which we find ourselves during the nine months of gestation and for the next twenty years or so. When our central nervous system reaches a sufficiently developed state, our senses relay inputs to our brain. The latter analyzes these inputs and produces outputs. Factors that may influence the outputs are: 1) the machine (primarily the result of our DNA and of how its program was run) and 2) our past and present environment at large. I see no other possible influences, and I therefore see no room for free will. That having been said, we can say that it is "us" that make each of our decisions because it is "the machine that we are" that decides (even if the decision is totally dependent on the physical state of the machine and the inputs it received). It's like a chess computer that analyzes and weights several options to finally make the move which received the highest weighting. In this case also it is the "computer" that plays. The fact that he is conscious or not when he plays his move is irrelevant here. The computer would not have been able to play something else than what he has played given its program, its physical state and inputs. So I think there is no way for us to make another decision than the decision we took at a particular time given our "biology" and the inputs received at and before that time. Now, if some events occurring in our nervous system are of stochastic nature, multiple possible outputs for a given configuration may exist but this does not imply "free will" because the result of the stochastic process is random, i;e. not controlled. (For guenuine "free will" to be recognised, I think  a gueniuine control, not determined by the machine should exist. If the machine is in control, the result of said control is determined by its genes and its environment. If the result is not "determined" but is stochastic, the machine is not in control. In both cases, no free will.) That's basically what I think about free will.