If chlorophyll or chloroplast is needed for the process of photosynthesis then how do non green plants with no chlorophyll get food
As @AlexDeLarge mentioned, all non-photosynthesizing plans are holoparasites because they lack the mechanisms for autotrophy. Although it is worth mentioning that it is not always chlorophyll that is doing the photosynthesis in all plants, and that even "non-green" plants can still photosynthesize (see note below).
There are generally two classifications of holoparasitic plants: those that require fungal mycorrhizal hosts called myco-heterotrophs and those that require other plants as hosts. Some examples of non-photosynthesizing myco-heterotrophic plants include those in the genus Monotropa. Examples of plant-specific holoparasitic plants include those in the genus Boschniakia.
In both cases, the parasite is partitioning nutrients directly from its host plant through a specialized root called the haustorium that penetrates the host's roots or hyphae, essentially bypassing the need for its own photosynthetic production. Technically, those parasites that attack other plants are still relying on photosynthesis (of the host), although indirectly.
This is a good review paper on some of these species: Leake JR. 1994. The biology of myco-heterotrophic ('saprophytic') plants. New Phytologist 127(2): 171-216.
Note: For instance, when deciduous trees turn yellow and red in the fall, they are relying on the carotenoids, xanthophyll and carotene. So, while the plant is not utilizing chlorophyll to absorb light, the carotenoid compounds are incapable of transferring light energy directly to the photosynthesis pathway themselves, and thus still require chlorophyll as a pass-thorough.