The Effects Of Changing Focal Length
When I was your age, we did not have zoom lenses, we used to zoom with our legs. Barefoot. In the snow.
So what is the effect of changing focal length vs. zooming with your legs?
Mike Browne has a great video explanation packed with examples on the impact that zooming vs walking has.
Basically it changed three things: Field of view, Depth of field and Perspective, as the vidoe so wonderfully demostrates.