HELP- Question on reinvesting loan interest

I am in the final round of the interview process for a private debt internship. I am required to complete a pre-employment project and am having some trouble. I was given loan terms and had to create a 60 month amortization model which was simple and I understand. The next step is to find an interest producing vehicle where the interest generated from the loan can be reinvested for an additional 60 months and model the returns from this reinvestment. Anyone have any ideas of how to go about this? I don’t have any experience in this type of finance and despite doing quite a bit of research I am still pretty lost. Any help would be appreciated