To complete all the Challenges in the Low Flying Garbage level in Episode VII – The Force Awakens in Lego Star Wars: The Skywalker Saga, you need to demonstrate some extra fancy piloting skills in the cockpit of the Millenium Falcon, during a battle over the Graveyard of Ships on Jakku.
Here are the three Challenge objectives, and how to complete them:
Getting Pretty Good at This: To defeat 3 TIE fighters in 5 seconds, maneuver so that you have a lot of TIE fighters in front of you and some distance away, then hold the fire button down and take three (or more) of them down in quick succession.
How Low Can You Go?: To lose or defeat an enemy by flying through debris in The Graveyard of Ships, fly through any one of the tubular pieces of wreckage lying about on the ground. This seems to pretty much guarantee that you’ll lose or defeat an enemy — you don’t have to lure one into following you closely or anything like that.
Not So Easy Without a Co-Pilot: To successfully evade a locked-on enemy bolt or missile, you first need to defeat the first two waves of TIE fighters. After you’ve defeated seven of them, and then ten of them, a new squadron armed with missiles will show up, and you’ll soon notice an enemy targeting reticule closing on the Millennium Falcon. Wait until the two halves of the reticule have almost come together, then press the shoulder buttons as prompted to perform a loop. This should evade the incoming enemy fire and complete the challenge.