The Passover Seder is guided by a printed program called the Hagadah. And an excellent guide for a Christian Seder by Alyce-Kay Ruckleshaus is available on Kindle
Passover is the first of the commanded feasts or appointments with God. It commemorates the deliverance of the Hebrews from slavery in Egypt. And it is observed in the spring of each year during the month of Nisan.