I have seen how catholic apologists run around scripture and the catechism making excuses for what they believe, but the simple fact is that there is no biblical support for infant baptism, and neither is there biblical support for baptism as a requirement for salvation.

In fact, what I have seen is catholic apologists edit their own bible for the so called 'original texts' to get around corruption, to promote corruption. (Catholic Answers)

"And as they went on their way, they came unto a certain water: and the eunuch said, See, here is water; what doth hinder me to be baptized? And Philip said, If thou believest with all thine heart, thou mayest. And he answered and said, I believe that Jesus Christ is the Son of God."

Now this scripture alone refutes both catholic doctrines on baptism, since belief is required in order to partake in water baptism.

It is further argued, that verse 37 is not scripture... yet the evidence in favor of including this verse is quite massive.
It is found in the Greek texts of Erasmus, Stephanus 1550, Beza 1598, Elzevir 1633 and Scrivener 1894. It is in manuscripts E, 4, 36, 88, 97, 103, 104, 242, 257, 307, 322, 323, 385, 429, 453, 464, 467, 629, 630, 913, 945, 1522, 1739, 1765, 1877, 1891, and others.

Acts 8:37 is in the Byzantine Greek text used by the Orthodox Greek Churches all over the world today.

It is also in the Modern Greek Bible and in the Modern Hebrew Bible.
The whole verse is also found in Old Latin manuscripts from the textline that predates any Greek manuscripts, including the Old Latin texts of ar, c, dem, e, gig, h, l, m, ph, r, t, w. Even the notes in critical text editions tell us that this verse existed in the Old Latin copies, the Coptic Middle Egyptian version, the Ethiopic, Georgian, and Slavonic, Lamsa's 1933 translation of the Syriac Peshitta and Armenian early Bible versions. It is also found in the Latin Vulgate and the Clementine Vulgate.

"Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost."

This is usually the very first response argument for water baptism. Let's take a look:

I'm going to use an analogy...

Johnny gave thanks FOR the gifts he received. Did Johnny give thanks for the gifts he was going to receive, or for the gifts already received?

We can establish the order of things by looking at other scriptures which confirm the order Acts 2:38 is speaking about. For example, if we go to the end of Acts 10, both Jew & Gentile which believed, received the Holy Spirit, but were only water baptized later on. In fact, they asked to be water baptized because it wasn't even brought up.
It should be noted, that it testifies that even those uncircumsized received the Holy Spirit when they believed, receiving remission of sin as per verse 43.

So Acts 10 supports water baptism being allowed FOR those who have already received remission of sin, and one cannot use the OT circumcision practice to create an infant connection to water baptism (As per Catholic Answers)

There is even another point I'd like to make.
As I was studying baptism a few years ago, I noticed something. Baptism doesn't necessarily mean water unless it says water.

Mark 1 amongst others, demonstrate that with Jesus' ministry, there will come baptism of the Holy Spirit, after the time of water. So these scriptures which are argued for water baptism, may be speaking of the Holy Spirit in most cases since they are after Christ's ascention.

I will provide some 'quick reproof' on those scriptures: