I realize that there are a lot of issues surrounding baptism and also that some Protestant denominations practice infant baptism. Yet, foregoing a long discussion on the various modes of baptism (immersion, sprinkling, etc.) let us differentiate Roman Catholic baptism, in particular, and Biblical baptism, not in how the water is applied but when and upon whom.
Typically, Roman Catholic parents will have their infant baptized as soon after birth as possible therefore, making it impossible for the baptized baby to accept or deny any Christian doctrines or Roman Catholic dogmas.