Achievement Name - Return of the Jedi
First, you will have to complete the 1st level of Episode 1 (Negotiations). This will then grant you access to all other episodes in the game.
There are 6 chapters in Episode 6:
1) Jabba's Palace
2) The Great Pit of Carkoon
3) Speeder Showdown - Vehicle Level
4) The Battle of Endor
5) Jedi Destiny
6) Into the Death Star
A 100% video guide can be found here:https://youtube.com/playlist?list=PLs9rvQZdz2r65Tz_wPJUwbV7W...
(Credit to HappyThumbsGaming)