Welcome to the tree! There is never a silly question.
The world of cloth nappying is even more complicated than when I started using them 8 years ago, I think we can all sympathise!
The simple answer is yes you can use the pocket wrap bit with prefolds or terries.
However, the pocket wraps are designed to fit an insert , usually a lot slimmer than a prefold or folded terry so if you stuffed that in the pocket it may effect the fit and you may get leaks. If you want to use over the top a prefold usually works better in a wrap with a gusset ( an extra bit of material at the leg hole) to keep it in place and catch poo.
Terries are bulkier than pockets it may not cover well.
There's no reason why you can't try, cloth nappying is all about finding what works for you and little one anyway.
Having used pockets, terries and prefolds I d recomend all 3 and having a mixture in your stash. Pockets were the most unreliable for us as they always leaked due to mine being heavy wetters. A two part system is what I would always opt for personally but everyone is different and every child is different.
The only other issue that comes to mind is that as I said earlier a prefold sits better in a gussested wrap ( eg thirsties, motherease Riki, nature babies) and terries and other fitteds are better in non gusseted wraps ( eg mother ease airflow) as their bulk is in a different ace.
Hope that helps!