Well, autotrophs are living things that produce their own food like plants. While heterotrophs get their food from other sources like the autotrophs e.g man
Autotrophs obtain their food from a process called photosynthesis. Energy is gotten from the sun, which helps them to manufacture their food. Well, according to the word photosynthesis, photo means light, and synthesis means combining or putting together. We all know that plants need light, water, air and nutrients to survive. This light needed is gotten through the process of photosynthesis. Energy is gotten from the light of the sun. Photosynthesis takes place in the leaves. It is also responsible for the green color. Hydrogen and carbon dioxide in the air are used to form food. Chlorophyll and some other pigments absorb energy from sunlight. All these can be proven by the reaction between water and carbon dioxide. They produce glucose and oxygen. Glucose is the food;
carbon dioxide + water→glucose+ oxygen
This reaction takes place in the presence of sunlight. Hope i helped.