Where ca I use JS DOM & Events?

Question

What and where is element.childNodes or element.firstChild, element.lastChild, element,nextSiblings, etc used?
Also, How is it used? Which Syntax? and ist applications in JS or HTML ?

Answer 1

When your target elements are grouped in a container element.

Answer 2

For more context
https://medium.com/@fknussel/dom-bom-revisited-cf6124e2a816

Answer 3

And can you please type in an example?