Is this lamp good for reading or as a desk lamp?

No. It is an accent lamp for a buffet or console. The black linen shade and decorative stem are meant for ambience, not focused task light.

What kind of bulb does it take?

The listing does not specify a bulb type or wattage. Check the socket and any maximum wattage printed on the lamp or its label before buying a bulb.

Will the antiqued gold finish match brushed nickel or chrome fixtures?

It can clash. Antiqued gold reads warm and traditional, so it pairs best with brass, bronze or wood tones rather than cool silver finishes.

Does the black shade make the light dim?

A black linen shade absorbs some light and gives a warmer, more contained glow than a white or cream shade. Expect mood lighting rather than a bright room fill.

Is it suitable for a bedside table?

It can work as a bedside accent, but there is no dimmer and no adjustable arm. If you read in bed, a lamp with a brighter, neutral shade is a better fit.