Items collected and cutscene

Good day to everyone,

I have created 7 scenes and in each scene the player must gather 7 items. How can I script this so that whenever he gathers an item, it can be displayed in the GUI (e.g 1/7,2/7) and upon reaching 7/7 to have a camera zoom in at the exit door which will be shown opening ?

(Using a first person controller camera, and have added a sphere collider with an is trigger for the items)

try this:
add an script on the item and add code in “OnTriggerEnter” function to
1.draw nums onGUI.
2.if collected all item then freeze controller and move the camera to door.
3.destroy the item