https://www.gamespot.com/articles/fortnites-secret-week-5-road-trip-challenge-how-to/1100-6461064/

Season 5 of Fortnite rolls on with another set of weekly challenges to complete. Once again, if you manage to clear all of the challenges in a given week, you'll complete a Road Trip challenge--this season's equivalent of the Blockbuster challenges from Season 4. Doing that, in turn, will reward you with a special loading screen, which contains a subtle hint pointing to the location of a free Battle Pass tier.

If you've kept atop all of the challenges available thus far this season and manage to complete the latest batch of objectives, you'll unlock a loading screen featuring characters posing in front of a dinosaur. The clue on this screen can be found on the sign near the dinosaur's feet, which depicts a house flanked by cacti with a Battle Star just above the roof.