While not much has officially been said about Fortnite Chapter 3 Season 1 by Epic, plenty of information is still out there. Thanks to plenty of leaks from places like Fortnite FN, we can see the contents of the Battle Pass already.
The trailer does confirm that the Battle Pass system introduced last season, where players earn Battle Stars, will be returning. Players can then use the Battle Stars to unlock the items from each page of rewards in the order they wish and will be able to move onto the next page after spending a certain amount of the Stars. Battle Stars are earned just by completing quests and leveling up.