I was brought up Catholic by m mother who thought it would be a good influence on me. My first episode of critical thinking was at the age of 8 when I was told by Sunday School teacher that no matter what you do in life, as long as you accept Jesus as your savior and ask for forgiveness, you can go to heaven. I remember thinking that was not right and it upset my sense of justice. I asked her even if I kill lots of people, I can go to heaven if I ask for forgiveness? When she replied yes you can, I responded with doubt and told her I did not believe her. She got very upset with me and tried to convince me that she was correct. I did not relent and she gave up.
I was still a believer until I was a young teen. I had been told for years about creation and Adam and Eve, but had also been learning about evolution. Since both were told to me by adults and said to be true I accepted them both, but had a difficult time reconciling the two. I kept trying to figure out if evolution occurred before adam and eve or after. Trying to combine the two ideas was not working and I became aware at 13, that they were bot competing ideas of existence and were not both true. I then began to evaluate both claims and realized I did not believe the creation story. That was the first domino to fall in my journey of critical thought. By 14, I was an atheist and have been ever since.