Why can't I play fortnite on my macbook?

I downloaded the epicgame app thing on my macbook, but it doesn’t want to launch??

Hello, thank you for reporting your issues with Fortnite. However, Answerhub is meant for issues relating directly to Unreal Engine 4 rather than our game titles. For assistance with Fortnite, please visit the following link:

http://fortnitehelp.epicgames.com/

If you cannot find the solution to the problem you’re encountering, please use the Email Us link on that page to contact Player Support for further assistance.