One thing I've always wondered about. The coronation is a semi-religious one. It is held in a church, and bishops and priests confirm him as King and Head of the Anglican Church. That's what I've wondered about- the dual roles- a constitutional monarch, and head of a religion. There's a built in conflict of ethics.
I wouldn’t say he or even his mother was "the head of a religion." It could be argued he will become the head of the Church of England, the Anglican Church, and able to appoint archbishops of that church.
But even that isn’t entirely correct. In reality the archbishop of the Church of England is chosen by a formal process that I think starts with the Crown Nominations Commission. Who then approach the Prime Minister with their recommendation, who in turn approaches the monarch, who then appoints the archbishop? As far as I’m aware, the monarch can’t refuse.
For the most part, I would say the monarch in official duties, works for the government.
When the Queen in 2018 was asked during an interview with Alastair Bruce, who she believed to be the head of the Church of England, she replied, "The Archbishop of Canterbury." This answer might reflect the Queen's “symbolic” position, and not necessarily the actual head.
From memory, I think the archbishop of the time was then asked the same question. I think his answer was, “God”.