1) A person can believe the words of a person. We can believe Jesus’ words about Himself and the saving Gospel. We can believe certain facts about who Jesus is and what He did for our salvation: He is the incarnate Son of God, the God-man. He died for my sins on the cross and was resurrected on the third day according to the Scriptures. We believe in Jesus’ Gospel. When we believe the Gospel, we believe in Jesus. Jesus is the Second Person of the Holy Trinity of God.
2) We believe in Jesus. When we do this, before or soon after, we learn of His death for the forgiveness of our sins, and His resurrection.