https://www.gamespot.com/articles/fortnite-season-5-challenge-guide-where-to-search-/1100-6460525/

We're into the second week of Fortnite Season 5, which means there's a fresh set of challenges to take on. If you're new to the game, this means that you can score some extra XP and Battle Stars for successfully completing specific objectives in-game. For the latest season, challenges are separated into two sections for Free and Battle Pass.

This week the free challenges, which anyone can do, involve dealing damage with assault rifles, searching seven ammo boxes in one match, and killing three enemy players in Paradise Palms.