Here "walk" is an metaphor for "live" and "flesh" is a metonym for physical life. Alternate translation: "we live our lives in physical bodies" (See: [[rc://en/ta/man/jit/figs-metonymy]] and [[rc://en/ta/man/jit/figs-metaphor]])
This phrase is a metonym for the way mortal people do things. See how you translated it in [2 Corinthians 1:17](../01.17.md). Alternate translation: "the way most people do" (See: [[rc://en/ta/man/jit/figs-metonymy]])
Paul speaks of his trying to persuade the Corinthians to believe him and not the false teachers as if he were fighting a physical war. These words should be translated literally. (See: [[rc://en/ta/man/jit/figs-metaphor]])
Possible meanings are 1) the word "flesh" is a metonym for physical life. Alternate translation: "fight against our enemies using physical weapons" or 2) the word "flesh" is a metonym for sinful human nature. Alternate translation: "make war in sinful ways" (See: [[rc://en/ta/man/jit/figs-metonymy]])