God Raised Him, Acts 2:22-24
There is no more important truth than the resurrection. Paul rightly declares in 1 Corinthians 15 that the entirety of our faith rests on Jesus' resurrection.
It is good and helpful for you to think about and work out issues of theology and doctrine. Those under the Lordship of Jesus rightly desire to be as obedient to His word and faithful to His commands as possible. Therefore, those who are disciples of Jesus spend their lives working out their faith and striving to understand God's word better. And yet the saving gospel is not complicated or hard to understand. Sometimes faith to believe is difficult, but understanding it is not. This is the beauty of God's grace; salvation is found through faith, by grace simple enough for a child to understand, powerful enough to save the most wicked sinner.
Acts 2 is the sermon that Peter preached on the day of Pentecost, nearly 50 days after the resurrection. He was addressing the people of Judea and specifically those who dwelt in Jerusalem. His sermon is simple and direct. Jesus died for your sin. God raised him from the grave. Repent of sin and believe that you might be saved.