These two week 3 challenges are called “Land a trick with a Driftboard” and “Get 3s of airtime in a Quadcrasher”. This video shows some reliable locations where you can find driftboards and quadcrashers.
Fortbyte #6 | Yay! Emote at an ice cream shop in the desert (Season 9 Fortnite)
Fortbyte #7 | Use CUDDLE UP Emoticon inside a Rocky Umbrella Location (Season 9 Fortnite)
Fortbyte #8 | Found within Junk Junction (Fortnite Season 9 Fortbyte Locations)