It will be an multi part interview question. After completing each task, the next task will build on top of your existing solution by adding or changing some use cases.
Best thing to practice for this is to be comfortable coding fast and remembering to make it a conversation between you and your interviewer. They are there to help you and not trick you because that would be a waste of everyone’s time. They want to see you succeed just as much as you do. Make sure to discuss your solution and listen for feedback from them incase they try to subtly steer you in one direction or another.
Focus on the current problem at hand without trying to optimize or abstract too many things in the beginning, you will have a chance to do that later if time permits. It’s better to get something down than nothing at all.
By the way, during the recruiter call he told me there would be two tech screens no matter what. So I did the first tech screen, and they decided to let me know that they wouldn’t be moving forward? What gives?