A:Answer Miguel,
We appreciate your interest in this CLX SET!
This system meets or exceeds the system requirements for Fortnite, and we would therefore expect it to run the game very well, even on high settings.
As to specific FPS rates, we can only speak in general terms, based upon the information available at this time (07/02/2019), but rates in the high 200's to low 300's, on low settings at 1080p, would not be surprising. Please note that various factors can affect this, such as connection speed, other programs running at the same time, server-side issues, etc.
If you have any additional questions, please feel free to contact our Friendly Customer Service Team at 855.490.2569 - we'll gladly help you find the best of our offerings here at Best Buy, to meet your needs!