This challenge is part of the Meowscles Mischief Challenges, the third agent Fortnite Chapter 2 Season 2 focuses on. You'll have to visit three specific locations: Shipwreck Cove, Yacht, and Flopper Pond. As with all challenges of this type, there is no particular difficulty other than knowing beforehand where to land.
Map
Shipwreck Cove
Hidden behind the mountains, this macabre beach is full of stranded boats. The place is of little interest in itself, but you can use the nearby zip lines to get around more easily.
The Yacht
This place is specifically mentioned on the game mini map. It's the lair of Meowscles, the agent honored during these weekly challenges. You'll find a lot of loot there. Be careful though, it's a contested site, guarded by henchmen!
Flopper Pond
As its name suggests, this landmark is full of fish schools. It isn't too contested and it's a good place to speed up fishing challenges without the risk of being bothered. You'll find it in the North East of Holly Hedges.
Once again, we recommend the Team Rumble mode, since you'll encounter fewer enemies. Remember that the challenge is to visit these places. Landing there or walking around will be enough to complete the challenge.