Cinematic Camera Movement

Hi everyone, so I am trying to prototype a unique camera system that gives a more cinematic camera angle and feel during gameplay. I want multiple cameras to be at fixed points in a level and then follow the player until the player passes through a trigger box which will activate the next camera. I tried to use the Camera Movement video tutorial, but unfortunately when I implemented that code with my own it didn't work. If anybody has any ideas it would be greatly appreciated!