As followers of Christ, you participate in water baptism just as Jesus did. In being immersed in water, you proclaim to the world your true identity now found in Jesus, just as Jesus proclaimed to the world who he was. This is an initiatory act. Certainly someone could step into the baptismal waters without being a true follower of Jesus, but this would not constitute a baptism. The reason to be baptized is to have union with Christ and his atoning work while proclaiming to everyone that God has given you a new heart and a new life. Faith and your adoption into the family of God is presupposed.
Additionally, just as John’s baptism of Jesus ultimately pointed to Jesus’ death and resurrection, so your baptism points to his death and resurrection. Paul tells us in Romans 6:1-11 that baptism represents how Jesus descended into the grave with our sin and rose to new life. And we get to participate in this! And not just in this symbolic experience, but in reality!
So even though Jesus commands that Christians should be baptized (Matt. 28:19), you should rejoice at this opportunity rather than see it as a duty. In baptism you have the privilege of obeying Christ, participating in a representation of his death and resurrection, and proclaiming to all that God saved you!