How does his father's absence from much of his life affect Obama in the text?

Based on Obama's anecdotes and personal thoughts in Dreams from My Father, his father's absence affected him negatively when he was younger, but later became a source of motivation. Obama had to learn his identity before he could create it, since he was a biracial child who grew up with his white grandparents. The absence of his Kenyan father made it challenging for him to connect with this African/black roots.
Obama also grew up with his Indonesian stepfather, whom he had pleasant relations with up until his stepfather's death in 1987. This made Obama even more curious about his own biological father. Obama also articulated what it was like to bear his father's surname while not having connections to the side of his family. It forced him to work harder to overcome obstacles without assistance from his biological father. Additionally, despite his father's absences, Obama became closer to his African roots due to his acceptance of being biracial in America.