This is indeed a Stephanotis, a beautiful tropical vine with fragrant white flowers. As a houseplant it grows best in bright, indirect light. Outdoors where there is no extended periods of frost conditions, your plant will thrive in part shade. Needs regular water and feed with a slow-release fertilizer formulated for blooming plants. When it matures, it will form seed pods such as yours that are 5-6 inches long and are shaped like green mangoes. In about 6-9 months, the pods will yellow and crack open revealing ripe seeds. However, once the seed pods form your plant will not bear flowers because it is expending all its energies into producing the seeds. If you are not interested in propagating the seeds, then suggest you clip off the pods so that your Stephanotis will bear blossoms.