Baptismal grace is the forgiveness of all sin, original and personal, and the communion with the Trinity. “The fruit of Baptism, or baptismal grace, is a rich reality that includes forgiveness of original sin and all personal sins, birth into the new life by which man becomes an adoptive son of the Father, a member of Christ and a temple of the Holy Spirit. By this very fact the person baptized is incorporated into the Church, the Body of Christ, and made a sharer in the priesthood of Christ. (Catechism, 1279)”

St. Paul describes the essential step to receive that grace:

Brothers and sisters: Are you unaware that we who were baptized into Christ Jesus were baptized into his death? We were indeed buried with him through baptism into death, so that, just as Christ was raised from the dead by the glory of the Father, we too might live in newness of life. For if we have grown into union with him through a death like his, we shall also be united with him in the resurrection. We know that our old self was crucified with him, so that our sinful body might be done away with,  that we might no longer be in slavery to sin. For a dead person has been absolved from sin. If, then, we have died with Christ, we believe that we shall also live with him. We know that Christ, raised from the dead, dies no more; death no longer has power over him. As to his death, he died to sin once and for all; as to his life, he lives for God. Consequently, you too must think of yourselves as being dead to sin and living for God in Christ Jesus.

Rom 6:3-4

What does Baptism mean? Baptism shows that burial with Jesus, which happens through the death of Baptism, causes the forgiveness of sins because Jesus rose as a new creature, and so does every person buried with him. That is the Catholic faith. It is observed that the cross and the immersion in water asphyxiate. They both literally take the breath away. Afterward, in both cases, the Spirit returns breath.

“Every time the faithful has their sins forgiven, it is because they entered into the death of baptism and are buried with Christ and rise with Christ (Rite of Penance).” The sacraments of healing, therefore, always include entering into the death of Baptism.