What the Bible says about  how we must make a fresh start

Jesus answered and said unto him, Verily, verily, I say unto thee, Except a man be born again, he cannot see the kingdom of God. (John 3: 3)

And Jesus called a little child unto him, and set him in the midst of them,

And said, Verily I say unto you, Except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven.

Whosoever therefore shall humble himself as this little child, the same is greatest in the kingdom of heaven. (Matthew 18: 2-4)