What the Apostles after Pentecost showed that we can do something about it - believe that Jesus paid the sin debt on Calvary, repent, and receive Christ as Saviour and Lord.
The twelve apostles did not preach the gospel of grace that Paul does.
It can be seen from Peter in Acts 2 what was being preached:
Acts 2:14 Peter is speaking to Jews and Gentile proselytes who are devout to the God of Israel see Acts 2:5 Acts 2:10 Acts 2:22
Acts 2:17 Peter says this is a fulfillment of prophecy for Israel in Joel in the last days before the day of the Lord.
Acts 2:30 Peter is saying that Jesus was raised from the dead, not for our justification as Paul writes in Romans 4:25, but rather to sit on the throne of David in his millennial kingdom on earth (Luke 1:32-33).
Acts 2:38 Peter tells them they must repent and be baptized in the name of Jesus for remission of sins.
Peter and the apostles preached only the name of Jesus (John 20:31), and baptism in his name, for the remission of sins, not the redemption of Christ in his death for our sins and resurrection for our justification, and faith in his blood for remission of sins (Romans 3:24-25).