Big 4 Business Transformation

Got an upcoming interview for business transformation internship at a B4. 

I have no exp in consulting whatsoever, prev internships were in finance/investments. My end goal is PE, I applied bc I've heard IB and consulting are both feeders. 

Can someone please shed some light on what biz transformation consultants actually do? I've looked online but the work does not seem that interesting to me, in case I was looking at the wrong place, I thought I'd post here to get the full picture. 

Thanks

Edit: If someone can also touch on what to expect for the interview, that'd be great.