I genuinely appreciate your sincerity. What you miss is that your entire argument depends on circular reasoning: you cannot use the Bible to persuade people who do not believe in the Bible.

As to why many people are not Christians, there are many reasons.

1. Today, the loudest self-identified “Christians” spout bigotry and hatred and reject everything Jesus Himself preached
2. Some people simply do not believe in the supernatural. For example, Thomas Jefferson believed Jesus was a good and wise man, but not God. He tried to follow Jesus teachings but was, mostly, an unbeliever.
3. People find other ideas, concepts, philosophies and/or religions more persuasive.

Before you can actually understand why some (actually many) people are not Christians, you’d need to momentarily lift your head from the Holy Book and talk to a variety of non-Christians, ask them and listen.