What is the relationship of human with god?

Why are we all here? what is our purpose in life? What are we supposed to do once we are born and what are the principles of life? Is there any book on guidelines of living a perfect life? These are some among the numerous questions which had been asked by philosophers and other spiritual persons from time immemorial. But have we ever wondered about the basic thing which remains hidden in these questions ourselves? If we think about it deeply, I believe we would come down to the fundamental propencity of enquiring who is god and what is our relationship with him? Did god created us or we are just a result of evolution of life on planet earth over billions of years? If we assume that god created us, what can be the purpose behind it... If he is so powerful then why would he need us to worship him, pray to him, etc. He is perhaps self-sufficient, a self-subsisting being, both formidable and respledent. I once believed that he created us in the lower domain, because he is all alone in the non-materialistic spiritual upper-domain, and aims to teach us life lessons by providing encumbrances in our path, so that we become like him so that he can share his feelings with us. Thats why he is also referred to as the great teacher in ancient scriptures. What are your takes on this? Do try to contemplate in your free time!