The English Reformation was part of a process and movement of thought, referred to as the Protestant Reformation, which led to the breaking away of a number of Christian churches in Europe from communion with Rome.
Each of the countries that went through this process did so in a different way, so the process in England was singular. Earlier the church had supreme powers. They had several malpractices, which included the selling of "Pardons" which when bought with money would make God forgive him (this also meant that they would not be punished). But then Henry VIII snapped ties with the Roman Catholic Church and he became head of the English church by what was called the Royal Supremacy and that was the beginning of the Church of England, although he remained a Catholic. For the first few years, the Church of England was almost exactly the same as the Catholic Church, except that it was ruled by the King instead of the Pope.
There were several causes for the English Reformation. One of these was that Henry VIII, who was King of England, want to divorce his wife, Catherine of Aragon. Another reason was because Henry wanted to control the lands that belonged to the Church. The Church was rich. Henry thought that if he was in power of the church he would be richer (and gain power).