Some translations indent each line of poetry to make it easier to read. The ULB does this with the poetry in 14:19-20.
Sometimes the names of places in Scripture are referred to by the name used during the time of the writer. For example, the location referred to as Dan was not yet known by that name because Dan had not yet come to live there. Moses, the author of Genesis, would have known this location as Dan.
Melchizedek was both a priest and a king. Because of this, he parallels the roles of Jesus. Melchizedek is an important figure in the book of Hebrews. (See: rc://en/tw/dict/bible/kt/priest)
Melchizedek worshiped the God Most High. This is probably a reference to the true and only God who created the heavens and the earth and came to be known as Yahweh. (See: rc://en/tw/dict/bible/kt/heaven)