For a challenge for week five in Fortnite's Season 9 battle pass, you need to grab a vehicle—like a Quadcrasher—and complete a lap on each of the map's three racetracks. There's a desert one, a snowy one, and a grassland one, and they're pretty easy to find.
The desert one is obvious, as it's been a mainstay on the map for a few seasons now, and it's just northeast of Paradise Palms. The snowy one is just west of Happy Hamlet, and the grassland one is between Junk Junction and the Block. Just grab a vehicle, head to each, and do one lap around the track to finish the challenge. Just make sure you wait until the race kicks off. You'll know when translucent checkpoints appear on the track.