Here "from the earth" means they are real people. AT: "four kings who will come to power on the earth" or "four men who will rise up from among the people of the earth and become kings" (See: [[rc://en/ta/man/translate/figs-idiom]])
# they will possess it
"they will rule over it"
# forever and ever
This repetition of ideas emphasizes that this kingdom will never come to an end. (See: [[rc://en/ta/man/translate/figs-doublet]])