When its off can i hold it at both ends and make that awesome whap sound?

You are the king of awesomeness.

How sturdy is the width of the belt? For example carrying things clipped to it (ie holster, knife, etc)

If your are fit then probably , if you have a bit of a belly then forget about it , used it for about 3 months before I switched to an edc belt and oh man , finally I can keep the holster on my waste (2 o’clock carry) . With this belt , my holster flipped couple of times and almost dropped it , too flimsy

Is the walnut buckle "wood" or "wood look"?

The walnut on the belt is actual wood

Is the material the webbing is made from stretchy like elastic or more like a seat belt material

It’s neither and both at the same time. There is a small amount of elasticity to it so the when standing from a sitting position, or sitting from a standing position, there is just enough “stretch” to accommodate the movement. It will stay snug to the body but not so much that it feels like it’s digging into your skin.