Understanding the Concepts and Benefit of being Born again

“Verily, verily I say unto you except a man be born again, he cannot see the kingdom of God” Jn. 3:4(KJV)
What does it mean to be born again? Jesus said unless one is born again, one cannot see the kingdom of God. Can a person be able to go back into his or her mother’s womb to be born-again?
How can this be, what is the mechanism behind this all? And is it true that you have to be born again to see God’s kingdom? This book has pondered all these thoughts and have outlined a fine write explaining the concept of what it means to be born again. God bless you as you read.