Well, you can keep looking through this thread for explanations, and they may be helpful.
But, there is a caveat, which is that Christianity is a revealed truth and its origins are supernatural. It is more than an organized system of philosophy, in the way the Greeks and Romans tried to invent their own religion after their traditional gods were reduced to the level of abstractions or metaphors among the highly educated of the time. While the Romans were attempting to create their own faith systems, the prophecies of the East (the Jews) were shrouded in mystery and ancient rite (such as the Passover meal, that was a precursor to the Holy Eucharist). and had origins going back for centuries upon centuries. While other pagan belief systems were localized and often undemanding, by the time Christ walked the Earth there were already far more Greek-speaking Jews living abroad than there were Jews living in Palestine. The faith had such powerful attraction that it had spread, even in spite of the old covenant being tied through heritage and blood, and before the Apostolic Age that opened the gates of the faith to the entire world.
So although our understanding and appreciation can be enriched & deepened with different insights, you are not going to ever find a totally complete, formulaic answer to, “Why did our Lord institute Confession? Why is it like such and such?”, or “Why did our Lord institute Baptism? Why does it need to be with water?” To some extent it’s something we need to accept as it is, and we have the Magisterium to preserve those elements of truth which are indispensable to the ancient Church.
Some ways to deepen our understanding would be through deeply reading the Old Testament and seeing the connections between it and the New Testament. The Levitical priesthood is especially important here, since we are on the subject of the Sacraments. Reading a book dedicated to Confession and its historic development would also be helpful. It is up to you. There isn’t a limit to how much you can learn.