Here "under" is an idiom that means to be under someone's authority. Alternate translation: "Eden ... assisted Kore in the cities of the priests" (See: [[rc://en/ta/man/translate/figs-idiom]])
Here "important" and "unimportant" are used together to mean "everyone." Alternate translation: "to everyone, including the important and the unimportant" (See: [[rc://en/ta/man/translate/figs-merism]])
This seems to imply the old and the young. This can be restated to removed the nominal adjectives. Alternate translation: "those who are old and those who are young" (See: [[rc://en/ta/man/translate/figs-explicit]] and [[rc://en/ta/man/translate/figs-nominaladj]])