Your question touches on the nature of the relationship between humans and God, which is indeed a deep and complex topic.
In the book of Job, Eliphaz's statement reflects a broader theological perspective that emphasizes God's transcendence and sovereignty. When he says that "man's goodness does not profit God," it suggests that God is not in need of human actions or morality to be complete or fulfilled. God is perfect and self-sufficient.
However, your thoughts about doing good deeds, praying, and reading the Bible highlight another dimension of this relationship. While it's true that God does not need our goodness to be satisfied, our actions can foster a deeper relationship with Him. Acts of kindness, prayer, and scripture reading are ways we respond to God's love, seek to align our lives with His will, and grow in faith.
From a theological standpoint, many believe that while God is not "profited" in the strictest sense by our actions, these actions can lead to spiritual growth for us and can bring joy to God. When we engage in good works or seek to deepen our relationship with God, we participate in a transformative process that can be beneficial for both us and the larger community.
In summary, while God's ultimate fulfillment does not depend on human goodness, our actions can reflect our love for Him, serve others, and enrich our own spiritual journeys. It's all about the relational dynamic between God and humanity rather than a transactional one.