What is the meaning of "Ach He'erich Es ha'Aretz"?
Radak: He imposed a collection on the people of the land.
Why does it say that he appraised "ha'Aretz" to give [only] silver, and approached "Am ha'Aretz" for silver and gold to give to Pharaoh Necho?
Malbim #1: Pharaoh Necho imposed his punishment. Yehoyakim accepted to give it. He had a Kikar of gold, but not 100 Kikar of silver, for Yoshiyah did not transgress "v'Chesef v'Zahav Lo Yarbeh Lo Me'od" (Devarim 17:17). Yehoyakim asked permission from Pharaoh Necho to collect silver from people. Later, he himself decided to also collect gold from the people.
Malbim #2: The punishment was primarily for making Yeho'achaz king improperly, before his older brother Yehoyakim. Am ha'Aretz did so. Presumably, the nobles supported Yehoyakim. Yehoyakim compromised. He imposed silver on "ha'Aretz" (everyone), and gold only on Am ha'Aretz.
What is the meaning of "Ish k'Erko"?
Rashi, Targum Yonasan: It is according to his wealth.
What is the meaning of "Nagash Es ha'Kesef v'Es ha'Zahav Es Am ha'Aretz"?
Radak: It means, he claimed from the people the silver and gold [that they were appraised to give].
