Let’s sue fortnite for many reasons

Oh no, they also have guns in Fortnite. 😠
Nah, it's healthy that games take inspiration from each other and improve their gameplay with it.
Fortnite is just a different game with a completely different playstyle and assets and feels much different compared to apex so there isn't any ground to sue them.

I'm sure Epic Games studio knows what they can and cannot develop their games without stealing any assets or code.
There isn't really a reason to hate a game just because they took inspiration of a game you like, they should be more of a compliment. 😉