I am applying for a PhD program and received a second interview invitation from my potential supervisor. She said she would like to discuss the potential direction of the project and my ideas for this project. My background isn't a perfect match with this project, so I have been working on the basic knowledge of this field (which is neurology). Before this interview invitation, I sent some emails to her to discuss some possible applications of the project, but all my questions were really general (for example, the project works on A, and I asked her if we can combine A and another therapy, B, together to expect an additive effect). However, most of them were less relevant to the main objective of this project, I asked them because I thought there could be more usage of the therapy A.
Do I need to come up with more specific questions about this project? How do I have impressive ideas for something I'm not familiar with?