One of the biggest reasons Step 1 feels overwhelming is that students try to memorize thousands of isolated facts, when the NBME is actually testing something much simpler: your ability to recognize patterns in the first 2–3 clues of a question stem.
NBME questions are not written to see whether you remember every enzyme, cytokine, or rare disease. They’re written to see whether you can sort a complex clinical presentation into the correct diagnostic “category” (the bucket) before doing anything else.