Answer:
. . . who suppress the truth in unrighteousness. . . (ROMANS 1:18)
GENESIS 3:4-7, JEREMIAH 17:9, JOHN 5:24
Well, think about it. It was 6000 years ago when the first person decided to believe a truth different from God’s. It was in the Garden of Eden — Adam and Eve believed Satan instead of God and they ate the forbidden fruit. When they disobeyed God, they showed us that they wanted to decide their own truth. Since then, men have sinned by ignoring God’s truth and believing different things. Our Bible verse tells us they “suppress the truth”—their heart does not want the true God. People believe so many different things because they are sinners and they don’t want to listen to God. The Bible tells us clearly that we must believe God’s Word. It tells us that if we don’t believe God’s Word we will spend eternity separated from Him.
My prayer is that you will come to believe the one truth that can save you by putting your faith and trust in the Lord Jesus who is the only way to God the Father and heaven. And you can be sure that if you have any questions about God, Jesus, or how to get to heaven, the Bible will give the answer. It is the true Word of God!
Source: https://answersingenesis.org/kids/worldview/people-believe-different-things/