I think “why the service line” is similar with why this role you applied. why you interest. I mentioned the service line here as the partner might ask you the structure of the role you applied. to see whether you ve done some research about it. for example technology risk is in the Audit advisory …you know . you can find the more details on Deloitte website.
for the skills you ve got, I think you can mention that in some of the questions. e.g.,“why this role” then you might say" I applied the role because… also, I believe I got the skills to tackle the challenge of the role.eg., prioritize skill I got from daily study. multiple tasks with similar deadline. interpersonal skill, comes from my experience of society. I use to organize events regularly" . partner might/would probe you any details depends on what you said.
so just relax and prepare about yourself. I think they want people have high motivation but also the capability you got. some times they might ask you at the end “is there anything you want to add?” then you might talk about why they should hire you. i.e., your career motivation and the skills you got (briefly mentioned).
however, all the suggestions are based on my personal experience. hope it is helpful to you.
good luck for your interview~~