Question 1: Who is the first and best of beings?
Answer: God is the first and best of beings.
Question 2: What is the chief end of man?
Answer: Man’s chief end is to glorify God and to enjoy him forever.
Comment: "Glorify" does not mean make glorious. It means [to] reflect or display as glorious. Other words you could use for "end" are "goal" or "purpose".
Question 3: How do we know there is a God?
Answer: The light of nature in man, and the works of God, plainly declares that there is a God; but his word and Spirit only, do effectually reveal him unto us for our salvation.
Comment: The question distinguishes two kinds of knowledge: one is natural and comes from conscience ("the light of nature in man") and from the works of God in nature; the other is spiritual or saving, and comes from the recognition of the true value of God and the beauty of his character. Natural knowledge is possessed by all people and thus makes all people accountable to honor and thank God. Spiritual knowledge is possessed only by those whose natural blindness has been overcome by the Spirit of God. (1 Cor. 2:14-16). Our children must come to see the difference between these lest they think they are saved by much natural knowledge about God—which the devils also have James 2:19).
Question 4: What is the Word of God?
Answer: The Scriptures of the Old and New Testaments, being given by divine inspiration, are the Word of God, the only infallible rule of faith and practice.
Comment: "Scriptures" is a special word for the "writings" of the OT and NT. Perhaps you will want to explain that the OT deals with God’s word that came before Jesus was born; and the NT is the word of God that came after Jesus was born. "Infallible" means it will never lead us astray in what it teaches. It is true and does not err. It can be trusted. "Faith" refers to right thinking and feeling; and "practice" refers to right doing. We measure our thoughts and emotions and actions by the rule of the Bible. "Inspiration" means that it is God-breathed: by his Spirit he guided his spokesmen to speak his word in their language.