Can someone explain how VTS works vs the retail index equivalent

I want to get out of the index as I understand it's a long term hold but the point at which we enter and exit when you don't know the exact price as it's nearly impossible to time is not what I prefer.

I'm looking at the VTS but there seems to be so few buyers and sellers, why is that? from the looks of it even if it is at a discount if there is no one to buy when I'm selling what is the point? Am I missing a different aspect here?

How do you also get a good grip of how it's converting from USD to the AUD equivalent?

from my understanding

The AUD we see in VTS is a conversion from the USD and also determined by any selling at a discount or whether it's at a premium. To work this out, we would need to convert from the exchange or spot at of USD to AUD at the time, and see whether it's at a discount or spot on.