What's the difference between variable valve timing ... what about the throttle?

Variable timing valve is a kind of valve technology; The throttle is a component of the engine. That's the difference.

I never post my answers on the website, but if I answer your supplementary questions, I will be exhausted. ....

You can do it yourself, and there will be many answers. And what I said must be much more detailed and formal than what I told you.