what are the roles of the king of saleem and the crystal shop

Melchizedek is the king of Salem, a mysterious far-off land. Melchizedek appears to Santiago in the town square of Tarifa, where he tells Santiago about the Soul of the World and his Personal Legend for the first time. Melchizedek always appears to people who are trying to live their Personal Legend, even if they don't know it.

Please ask about each person one at a time.