Question

How do water come in coconut

Answer 1

coconut has liquid endoplasm so the water is synthesized by the plant itself during fruit formation

Answer 2

coconut water is the liquid endosperm in young coconuts. At a later stage in addition to free nuclei, several cells enclosing variable number of nuclei are formed. Gradually these cells and free nuclei start setting at the periphery of the cavity and layers of cellular endosperm start appearing . At this stage coconut is called tender coconut .As it matures the quantity of cellular endosperm  increases and the number of cells also increases due to cell division