I always used to wonder this, but there is actually a really easy way to do this.
Okay so, all you have to do is preview the part you want to modify the zoom, then if you look at the preview screen, on the right side of the preview screen, there will be these button type of things (>1 line, >>10 lines, Navigation, Story Modifiers, Line-By-Line Mode, Show Helpers)
Press on “Show Helpers” then more buttons will show up (Camera, Spot Directing, Speech Bubbles, More Helpers)
Then press on “Camera”
Once you do that, on the left side on the screen will pop up new buttons **(Zoom, Focus, Reset)
Play around a bit with those buttons.
Zoom = Zoom in and out
Focus = Moves the camera up and down and side to side
Reset = Resets your zoom back to 150 150 to 100%
After your down with that, you need to enter the command into your script.
So scroll down under the preview screen to find a white box with little words on it.
Press the button “Copy” and then after that press on the paste it in your script.
Hope this helps!