Writing a journal paper

Hello, I am starting to write an empirical paper from my thesis. For that, I am taking 2 objectives and research questions out of 5 from my thesis.
Its turning out to be a tedious task, what do I include, what do I don’t include? As, the objectives are quite interrelated, I am confused as to how should I divide the content. According to my supervisor, I at least need to write 4 research papers. I have also not completed my thesis writing yet and writing one journal paper is turning out to be so time-consuming, how can I write 3 more?
Any advice?