Upvote:0
Croatia is not in the Schengen area. You need a separate visa for Croatia (unless your citizenship means you don't need a visa for Croatia).
Upvote:2
As you indicate in a comment, you will not need a separate visa for Croatia if your visa meets given requirements.
But the officials who check out your visa application for France will not consider your travel to Croatia as part of your travel plans for this visa.
So you give your details for your travel in the Schengen zone without mentioning Croatia, do mention it in the overall itinerary, where there is place to mention it.
If you do not get a visa that allows you to visit Croatia on your Schengen visa, you will need to apply to a separate Croatia visa.