Read scripture. Research the history, beginning with the Catholic church. My understanding has always been that baptism is essential. (Mark 16:16) But make sure that you understand why you're getting baptized. The New American Bible (School and Church Edition) has been the most helpful to me; and I've been reading scripture, since age 6...yes, the "children's Bible", and King James at 9.
I refer to Catholicism as an incomplete gospel and that is as polite as I can come without repelling Catholics. You have to be born from above which is not baptism but being born again means different things to the Catholic.
I fought the baptism debate for years and I have four printouts of my debates that equal the size of a book and it is quite a lengthy debate but you'll never prove to me or win a debate where you become Christian by being baptized. Start a new thread and address me if you wish to go down that road but I'll give you an introduction and I also have all the arguments written down and I can win but first look at this introductory information:
Meaning of the Word Baptize
Do Mark 16:16 and John 3:5 Teach Salvation by Baptism?
Do Acts 2;38 and Romans 6:4 Teach Salvation by Baptism?
What Is Required For Salvation?
1 Peter 3:21 The like figure whereunto even baptism doth also now save us (not the putting away of the filth of the flesh, but the answer of a good conscience toward God,) by the resurrection of Jesus Christ:
A "like figure" in 1 Peter 3:21 would be the equivalent to a photograph today. Photographs don't create history or make history happen. Photographs only record a past or present reality. Photographs don't create present realities so that is a big part of my argument why Baptism does not save a person.
Baptism doesn't represent life because it represents DEATH:
Romans 6:4 Therefore we are buried with him by baptism into death: that like as Christ was raised up from the dead by the glory of the Father, even so we also should walk in newness of life.
There are these other symbols of baptism:
1 Corinthians 10:2 And were all baptized unto Moses in the cloud and in the sea;
We have this symbolism. Noah is also a symbol of baptism. The eight souls in the ark were baptized. The people outside of the ark were baptized too and died. You have to put your faith in Jesus (the ark) because everyone outside was baptized and died just like millions of Catholics will be baptized and die in their sins because they aren't saved.
Matthew 7:21 ¶ Not every one that saith unto me, Lord, Lord, shall enter into the kingdom of heaven; but he that doeth the will of my Father which is in heaven.
You want to go to heaven? Don't be misled.