You'll need to unlock the Dodo before you can spawn it in single player story mode using this cheat. In order to unlock it, you need to complete the 'Sea Plane' random event. To start the random event head over to the area that is just to the East of the Alternate Farms (Ron Winds). You'll find a mountainside cove there and can begin the event.
https://www.youtube.com/embed/kmKmvwZIHfA
Before we forget though, the random event is only available on next-generation versions of GTA 5... meaning that you'll need a PS4, Xbox One or PC in order to firstly unlock the Dodo Airplane and then secondly to use this cheat to spawn (no bueno on the PS3 or Xbox 360). The Dodo is a heck of a lot of fun though, so the effort is worth it!
