The 420 bus services Sydney Airport, but this doesn’t run to or with the CBD. The 420 operates as much as Mascot, or Burwood in the opposite direction. You can take a bus from Sydney Airport to Mascot and hook up with town by using teach as we’ve outlined over, https://sydney-international-airp46737.illawiki.com/1060123/sydney_international_airport_taxi_limousine_an_overview