Baptism is kind of like a wedding.
When you love someone and you want to spend the rest of your life committed to them exclusively, you have a wedding ceremony. It’s a public statement which declares your love for each other before God and to all your friends.
When you love/follow Yeshua and want to spend the rest of your life committed to him exclusively (in the spiritual sense), you have a baptism. It’s a public statement which declares your love for him before God and to all your friends.
It’s a way of saying publicly that you are a Christian and you take that seriously, and you intend to keep doing so for the rest of your life.

How you “do” baptism isn’t really important. It’s a symbolic thing. It’s the public statement that is important.
But in the Bible, it does seem that baptism usually involved someone being physically immersed (completely under) some water like a river or lake, and then being brought up again.
That makes sense because this symbol of baptism represents how you also died with Christ on the cross and were buried and resurrected with him.
This bit may be hard to comprehend right now as a young Christian, but in some way you died 2000 years ago! You (in fact all Christians) were in Yeshua when he went to the cross and so, when he died, you died.
So of course, when he rose again, you rose again. You were effectively born again.
Don’t worry if you don’t get that bit right now. You will in time. Until then, just think of baptism as a way of publicly declaring your decision to follow Yeshua.

In Bible times, if you stood up publicly and said, “Hey everyone, I’m a Christian now.” Then you may well lose your job, or even your life.
It was a big deal to declare that you were a Christian in those days. So people wouldn’t doubt anyone that said they wanted to be baptised, and they were usually baptised that very day.
These days it’s not such a social and political risk to declare that you are a Christian, and some people who are not Christians still want to be baptised. (Usually they don’t realise what it’s really about and just want to fit in).
Because of this, most churches ask you to do a short Bible study course before they baptise you. This is not really necessary from a Biblical point of view, but it’s just their way of feeling like they made sure you were really a Christian before they baptise you (and basically publicly declare that they think you are too). It’s not necessary, but if that’s what your church wants then go along with it. You might learn something anyway, and at least you’ll meet the pastor and some other Christians.

Matthew 3
Acts 2
Acts 8
1 Peter 3

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