Do I need hose clamps for this?

Yes. You'll need clamps rated for silicone hose on both the inlet and outlet ends. Spring clamps or worm-gear clamps both work—pick whatever fits your hose barbs.

Can I use this for coolant, boost, or vacuum lines?

All three. The 3-PLY construction and silicone material handle coolant temps, turbo boost pressure, and vacuum draw without issue. Just size your clamps appropriately for the application.

Does this hose need prep or sealing before installation?

No prep needed. Slide it over your barbs, clamp it down, and you're done. Silicone doesn't require priming, painting, or surface treatment.