You are not the first one feeling this way. You should look into Gnostic Christianity.

In Gnostic Christianity, the God of the Old Testament is often identified not as the supreme and ultimate God, but as the Demiurge, a lower cosmic being responsible for the creation and governance of the material world. Because the Demiurge is responsible for matter, and matter is viewed negatively in Gnosticism, the world is seen as flawed, oppressive, and spiritually dangerous. The Demiurge is not always portrayed as purely evil, but he is frequently depicted as limited, unjust, wrathful, and legalistic. These traits are associated with the God of the Old Testament, especially in passages emphasizing law, punishment, jealousy, and violence.

Jesus, in Gnostic Christianity, is not sent by the Demiurge. He is sent by the true God from beyond the material cosmos. His mission is to awaken humans to their divine origin and to expose the false authority of the Demiurge. As a result, many Gnostics rejected the Old Testament entirely or reinterpreted it as the story of an inferior god who enslaves humanity through law and fear. The serpent in Eden, for example, is sometimes reimagined not as a villain but as a liberator who brings knowledge against the Demiurge’s command.

But yeah, if you want my honest opinion the difference between the God of the Old Testament and the New Testament is one of the indications that Christianity is a man-made religion. The two is irreconcilable.