The test is NOT adaptive. They are considering making it adaptive in the future but it is not for now.
All students do not get the same set of questions.
There is speculation about how questions are assigned to individual test takers but most people agree that the NBME has a huge bank of questions (around 10,000 from some estimates.) The disagreement is in whether there are several different forms of the exam which each student getting a different version but students getting the same versio n having the same exact test or whether the questions all have assigned difficulty ratings and each student gets a random mix of questions but the same amount of easy/medium/difficult questions as any other student. As with many other things surrounding the USMLE, this remains a highly guarded secret of the NBME.
The way I approached it is like poker. Gotta make the best of the hand you're dealt. Don't spend your time thinking about hwo some people got more path questions and you happened to get stuck with more biochem. Such is the luck of the draw if it happened it happened, nothing you can do to change it. So be ready for whatever they can throw at you. Study everything. Make the most of the questions you get. Good luck!