The parent comment covered it well, but just to make a point: the goal of preparing is to make sure the interview process goes smoothly. Assuming the interview

The parent comment covered it well, but just to make a point: the goal of preparing is to make sure the interview process goes smoothly. Assuming the interview is soon, there's only so much preparation you can do for technical questions in a short period of time. You can't be much more prepared for the technical questions than your current level of knowledge, so the preparation is more about making a good impression based on interpersonal factors.