Presbuteros most certainly IS in the New Testament and that is the root word of the word ‘priest’.
Uh, what does “kohen” mean in Greek, then, and why is this used in the Old Testament for “priest” and not in the New Testament?
Because the actual term in the New Testament you are claiming as “priest” means “elder.”
Actually it means Elder. There is a specific greek word for priest and it is not presbuteros