Statistical analysis:FD, FC, FDC

I am based on“ Fibre density and cross-section - Single-tissue CSD — MRtrix 3.0 documentation ” This webpage steps to perform statistical analysis of FD, FD, and FDC.
But I didn’t create the subjects folder. I only used DWI data from a normal human brain and directly preprocessed it. However, during this step, an error occurred.

Does this mean I need more images?
If I create the subjects file in the first step, can I solve this problem?

If you create a subjects file, where 001_ Control/dwi.mif can be set to represent computer images of healthy individuals, study/subjects/021_ Is patient/dwi.mif set to the patient’s brain image?