Cake in homemade chocolates
I am inferring you have coated the cake with chocolate, as some sort of petit four or confection.

This will not change its shelf life.  It will still stale inside the chocolate (as this is a function of the change in hydration and gelation of the starches), and while less likely, pathogens may still grow since they will have been present from before the cake was enrobed with the chocolate.

Depending on the type of cake, it should be good for between 1-4 days or so, refrigerated.

Cakes freeze exceptionally well.  If you wrap your confections tightly to prevent condensation when thawed, you should be easily able to hold them for several months.