Is this door solid or hollow?

The listing gives stile-and-rail construction and a 1-3/4-inch thickness but does not say whether the core is solid or hollow. Confirm the core with the seller before ordering.

What does prehung mean here?

The door arrives mounted in its frame with hinges, as a complete unit. That differs from a slab, which is the door alone and needs separate jambs and hinge cutting.

How do I pick left or right hand?

Stand on the side the door swings toward and note which side the hinges are on. Confirm the swing direction against your opening before ordering.

Does it come with a lockset or handle?

The listing does not state that a lockset or handle is included. Ask the seller what preparation the door has for your chosen hardware.

Will it fit my existing frame?

A prehung unit replaces the frame, so the rough opening, wall thickness and jamb depth must match. Door size and rough-opening size are different measurements.