We have the choice to control ourselves or let go of control. Control is something very difficult to learn and also something not normally noticed by many people.
If there are things in the past, that made you mentally ill and resentful, you still have the choice to learn to control youtself.
If there is something in your DNA making your character a certain way, you still have the choice to learn to control yourself.
This is the power of will. This is the difficulty of life.
Freedom of course is another question and very subjective for everyone.
Remember that science as well as philosophies are just systems made by people to perceive the actual world as best as they can.