As the birth approaches, I worry I will not be able to be a good mother or father. What can I do?

That worry is itself a sign that you care, and a good intention along with effort is enough in the sight of Allah. No parent is perfect; what is required is to try, learn and pray, not to be flawless. The strength to care for a child usually grows along with the responsibility, little by little. Start learning the basics of caring for and raising a child bit by bit, and ask experienced parents for guidance. Make plenty of supplication asking to be granted offspring who are a comfort to the eyes. Face one day at a time, rather than imagining every difficulty at once. See du'a & prayer.