Is a heterotroph is an organism that produces complex organic compounds from simple inorganic molecules using energy from light by photosynthesis.?

No, that description actually defines an autotroph, specifically a photoautotroph, which uses light energy to convert inorganic molecules into organic compounds. A heterotroph, on the other hand, is an organism that cannot produce its own food and must obtain organic compounds by consuming other organisms or organic matter. Examples of heterotrophs include animals, fungi, and many bacteria.