The 5 Branches of Philosophy
Life As the Moral Standard
Reason Is Man's Means of Survival
Harmony Of Interests
Every existent acts causally in accordance with its identity from electrons to brain neurons to conscious minds. The world is entirely determined in a physical sense, but the question of free will boils down to a question of context.
Within the context of your mind, your consciousness is not a bunch of atoms held together in a particular way, but a perceptual and rational faculty that processes percepts into concepts from the lowest to the highest. This includes the creative process and problem solving. There is never something created from nothing -- there is no such thing as a divine inspiration; it is all a rearrangement of what was previously there.
Both within the context of consciousness and the context of interpersonal relations, people do have free will. This means that they do make choices, they act on those choices, and they are responsible for those choices.