Remember, it may turn out to be the case that Milo the robot already has free will, and the scientist, for some reason, hasn't noticed or realized that they have already created a free-willed robot.
For reference, remember that the existence of free will means that an entity has a "will", which is an internal faculty of being able to decide for itself what it is going to do, based on it's own ideas and goals, and that it also occasionally has the freedom to act on its own decisions, rather than being coerced by some external force to do things it would not, on its own, decide to do. (Added 3/14/23.)
(Added 10/10/23)
1. A will is a mechanism inside a specific being that allows that being to form preferences, desires, and intentions, decide between different courses of action, and initiate their own actions action on those decisions.
2. Coercion is when, by force or threat, one
being completely imposes their will on another
being, making them do something they would otherwise
never do. Unlike influence, constraint or restriction, coercion
removes a beings freedom of action, placing them in a situation
where they have no other choice
3. Freedom is a condition in which a being, while perhaps subject to various influences, constraints, and restrictions is still able to pick out and perform the action that they most think they should do, out of a range of several possible actions. Freedom is thus basically the absence of coercion.
4. Free Will is when the will is at least sometimes
free. If robot Milo ever gets to act on their own decisions,
without being forced by others to do things they don't want to do,
then Milo has free will. If it is the case that
Milo has no will, or that Milo's every action is
always coerced, then Milo has no free will.
If you accept that it is technically possible to create a robot with free will, then you will have to say just what kind of mechanism would have to be installed in the robot's brain, or what it already has in its brain, in order to give it exactly the same kind of free will that human beings have, or appear to have.
If you do not accept that it is technically possible to create a robot with free will, then you will have to say just what kind of mechanism you think human beings have that gives them free will. (If you want to talk about why a robot cannot have this mechanism, you will have to do more than just say "machines can't do this." You will have to say what this mechanism is, and why something that a human brain does using neurons and synapses cannot be done with some mechanism that does the same things as neurons and synapses.)