You honestly don't seem to grasp the implications? Say a volcanic eruption happens 6000 years ago. How exactly is anyone (like me or yourself) going to know it didn't happen 1.2 billion years ago...................? You are going to date the materials under the assumption that the strata, rocks, etc., are millions or 100's of thousands of years old. THERE IS NO ONE AROUND TO TELL YOU WHEN THE ERUPTION HAPPENED or the STRATA WAS LED. Your assumption inevitably is that any of the material you find is ancient unless you are informed otherwise. OKAY, GOD has informed me through HIS word that (in all due respect) that the world is most likely only thousands of years old. I believe HE is right and your assumptions are in error because no one is alive to determine when any ancient evens actually occurred; however, you are aware of the Mt. Saint Helen event ---- but what if you were not?
I see you don't think much of scientists but they are not stupid, they don't assume anything unless there is evidence to support it. Radio-isotope dating is one dating method but there are many. In areas where there are annual dry and wet seasons you can see this reflected in tree rings and lake sediments that can be counted.
The world may only be a few thousand years old but it certainly LOOKS much, much older. For instance, mountains rise and erode, we can see the evidence for ourselves. It is hard to believe the Rockies were raised in just a few millennia or that the Appalachians rose
and were eroded in the same time frame.