Fore Loss Prevention, I would say research the company a bit, get to know what there company is about. Afterwards, research what certain words mean like for example shrink or shrinkage. They are real words they mainly stand for shoplifting, employee theft, supplier fraud, and errors in paperwok.
Normally the bigges tip for anyone is have the right attitude for what they desire, like customer or guest oriented, always willing to help, and they will throw in real scenarios that could hapen in the store ad what the questions like what would you do in this situation or that situation.
For example being a prior security officer in residential, casino, and or retail helps, also yes prior military, and law enfrcement background. Knowledge in cc-tvs, but this will depend on many factors since there are several different cameras out there.