Opto ergo sum, Latin for I choose therefore I am.
Regardless of the claims to the contrary, if you can choose, then you have free will. Your choice determines what you become. If you choose to eat a hundred hamburgers a day for a year without exercise then you chose the outcome of becoming obese.
Three main influences that change you are your thoughts, actions and experiences. If you choose to think negative thoughts every day, you chose the outcome of a negative life. If you choose to hug a hungry polar bear, you chose your death. If you choose to experience a war, you chose the outcome of psychological trauma.
At the age of 18 humans leave the safety of their mothers as independent agents, from that moment self is responsible for their choices and the outcomes of those choices.
Everything is in a state of becoming. You determine the outcomes by your choices of what you will become now and in your future.