The phrase "first bullet" refers to the initial or primary action or option in a series of choices or tasks. It represents the first and typically most significant step or decision to start something. Full definition
«This individual's first bullet point packs the biggest punch and, by design, he put it at the top of the list,» he said. (theladders.com)
This is just elaboration on the very first bullet point - the goal is to reduce regulatory burden that artificially (intentionally) curtails domestic energy supply on the carbon side. (politics.stackexchange.com)
A year and a half ago, I opened up the first page of my brand new Leuchtturm1917 dot grid notebook and began my very first bullet journal. (mindbodygreen.com)