So, you have demonstrated free will within a predestined end to your life here on earth.
It is given unto man once to die and after this the judgment.
Our mortality does not come from God but from our separation from God. God did not bring death. We did. Mortal parents give life to mortal offspring. It's not predetermined; it's our (fallen) nature.
You also treat life as this, physical life, on earth. We believe that real life is life in communion with God; that we get life only through God and that life in God is eternal. We also believe that all the saints are alive and are fervently praying in the Church Triumphant for us, sinners, that we may repent of our ways before physical death, and come to God. Real death is eternal separation from God.
Whether we live or die is left to us. God offers eternal life, and a Way to all mankind. So many refuse it. No one is forced by God to live or die.