How can I recreate this
Without telling you exactly what to do - the way I would approach it would be to look at using trigger volumes and the player, and either use a timeline to move the platforms/stairs position as a player enters/leaves the trigger volume, or sequencer (Unreal’s replacement of Matinee).
Trigger volumes:
Timelines:
The tutorial on moving a door may give you some inspiration
Tutorial on moving a door with Matinee
There may be an easier way to do it but that might get you started 