Walking is a metaphor for living. AT: "conduct your life in the power of the Holy Spirit" or "live your life in dependence on the Spirit" (See: [[rc://en/ta/man/translate/figs-metaphor]])
The phrase "carry out someone's desires" is an idiom meaning "do what someone desires." AT: "You will not do what your sinful nature desires" (See: [[rc://en/ta/man/translate/figs-idiom]])
The sinful nature is spoken of as if it were a person and wanted to sin. AT: "what you want to do because of your sinful nature" or "the things you want to do because you are sinful" (See: [[rc://en/ta/man/translate/figs-personification]])