Save The World is $8.99 on Xbox and PlayStation stores and it includes the base game along with quests that allow you to earn up to 1000 V-Bucks : r/FORTnITE
Fortnite V-Bucks $36.99 [Digital] VBucks 36.99 DDP - Best Buy
How to Buy Fortnite Save the World with Xbox Gift Card – Should I Buy Save the World or V Bucks? - YouTube