Vocal Cords (Vocal Folds) and How They Work

As for your voice, air pressure serves as the power supply, the same as in other aerophones:

You take a breath and, as you let it out, the air pressure sets your vocal folds (also called vocal cords) vibrating.
A column of air (the intermediary) inside your respiratory tract, elevated in pressure, transmits the vibrations of your vocal folds to several resonators: the hard cartilage of the trachea (windpipe) and bronchial tubes in your chest, the bones of your rib cage, your pharynx (throat), and the various bones in your head.
These resonators, being much more massive than your vocal folds, amplify the vibrations of your vocal folds.

(The above is a rough description. There’s no unanimous agreement on precisely how everything happens in the production of human vocal sound.)

The consonants and other sounds you require for speech and singing depend on how you position your tongue and shape your oral cavity.