Each letter is made of metal/wood/acrylic, with a pendant cord + bulb holder through or under the letter. Usually E27 Edison/St Filament bulb - warm white 2200K-2700K for that cozy glow.
Mounting:
Ceiling-suspended, one cord per letter. Needs high ceiling 2.7m+.
Wall-mounted, spotlights pointing down. Saves ceiling space.
Most are powder-coated black metal like in your pics. White/gold also available.