They need to find energy and chemicals by growing on a source of food. Then they release chemicals on the food they are eating. This chemical works something like your digestive juices in your stomach. The chemical digests the food and the fungus re absorbs it. Yeast and mushrooms are types of fungus.
Plants are organisms that can make their own food.
They have lots of cells that are very specialized. There are many kinds of plants from simple to very complex. Some plants that you know are mosses, ferns, algae, flowering plants. Animals are many-celled organisms that have specialized tissues and organs. Animals must search for their own food.