What the Bible says on how to become a child of God:
WHO HAS SINNED? "For all have sinned, and come short of the glory of God." (Romans 3:23)
WHERE DID SIN COME FROM? "Wherefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned." (Romans 5:12)
WHAT IS THE PENALTY FOR SIN? "For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord." (Romans 6:23)
IS THERE A WAY OUT? "But God commendeth his love toward us, in that, while we were yet sinners, Christ died for us." (Romans 5:8)
"That if thou shalt confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved. For with the heart man believeth unto righteousness; and with the mouth confession is made unto salvation. For the scripture saith, Whosoever believeth on him shall not be ashamed."
"For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life." (John 3:16)