Free Will, is in effect regardless of what forces are in play around us.
The other side argues that there's no such thing as free will because everything is quite simply matter in motion. You could argue quite naturally that everything is made of particles and particles are always in motion, and this past motion causes future motion. So it just so happens that when you receive some kind of stimulus, that stimulus affects you in such a way that causes you to act the way you do - so the stimulus determined your response. If you get down to it, then perhaps with a visual example - maybe the exact absorption of photons by your retinas fires the exact combination of cells that fires the exact combination of neurons which codes your response. So if even one photon was slightly off, then the momentum of that photon hitting/or missing that protein in your retina could cause a slightly different reaction. This is just one, extremely tangible example, but you could extend this example behind everything you've done, and behind everything that's ever happened as the result of particles bouncing off each other the certain way that caused the specific situation of the world as we see it now.
So even free will is the result of particles in motion - perhaps causing the situation for your parents to meet, and then causing the fusion of that specific egg and that specific sperm that gave you your specific gene combination - and every event between those two, and every event that came after, which ultimately determined your strong belief in free will. I don't think we can call particles random in the most strict sense, because every action has a reaction, not multiple reactions. If I hit a wall to the north of me with 5 newtons, my fist will receive a force of 5 newtons south, and not any other reaction.