They can be classified as either atheist or agnostic.
an atheist is a person that does not believe in religeon whatsoever
You would call such a belief a heresy. Depending on the nature of the belief, it might also be called blasphemy.
athiest
A tolerant person.
A Pilgrim.
A person who believes all religions lead to the same place is often referred to as a religious pluralist or an interfaith advocate. This perspective is rooted in the belief that all religions are equally valid and ultimately lead to a common truth or destination. It emphasizes the importance of respecting and understanding diverse religious beliefs and practices.
You might call that person an ascetic, or an eremite (hermit).
A person who goes on a trip for a religious purpose is commonly referred to as a pilgrim.
A person who travels to a new place in search of religious freedom is often referred to as a religious refugee or pilgrim. They may also be described as a seeker of religious sanctuary.
They could be called either a fanatic, a zealot, a devotee.
Japanese people are mainly religious believers in Shinto or Buddhism, and Christmas is a Christian/Western holiday/belief.
For religious people, God. God would have to be the most well known person ever. Every religious person in the world believes in some sort of God no matter the name they call him or her. Even if your not religious you've herd of God.