How do I take care of an orchid? I know they are air plants... Some of the roots on mine are hollow. I also know they need little water and like humidity, so I've placed it in the bathroom close to a frosted window.
There are literally thousands of types of orchids. Some of them are naturally epiphytes, that is, they live on branches of trees and derive most of their moisture and nutrients from rain water and air. Others are terrestrial, naturally living in soil. It sounds as though you have one of the epiphytic types.
Light needs of orchids can also vary greatly, but most adapt pretty well to bright filtered light.
Without knowing specifically which species of orchid that you have, it sounds as though you have selected a pretty good site for yours.