Autotrophs belong to

An autotroph is an organism that can produce its own food by photosynthesis using light, water, carbon dioxide, or other molecules. They are known as producers because they make their own food.
The food chain is a system of individuals or groups of organisms that get their food and energy from organisms in the previous trophic level. 

Producers (autotrophs) make up the T1 (first trophic level) level of a food chain. 

Primary consumers make up T2, secondary consumers make up T3, tertiary consumers make up T4, quaternary or top consumers make up T5, and decomposers make up T6.