Your Protagonist. Besides the antagonist, there are many other external issues that could hinder the protagonist’s journey to realizing their desires.
Action Plan: Answer the above questions to make a list of all the external factors that will conspire (consciously or no) to make things worse for the protagonist over the course of the story, including the antagonist. What does a struggle against that thing, those people, or that faction look like? What victories will these people/things achieve to create setbacks for the protagonist, and what will it take for the protagonist to overcome them? Will it take one exciting scene, or many scenes of slowly chipping away at these antagonist forces before the protagonist overcomes them? If you’re not doing first-person narration, are there any scenes you want to devote in your story that show the threat these things pose in order to raise the stakes? Add any scenes you come up with to your list of essential scenes, which we’ll begin to deal with later this week.