Have you ever helped plant a garden? Did your hands get dirty? "Dirt" is another word for soil. "Dirt" is something we might not want. Soil, on the other hand, is very useful! Without soil, much of life on Earth would die.
Plants need soil. Soil holds up plants. Plants get water and nutrients they need from soil.
Many kinds of plants are food for people. Other plants are food for animals. Without soil, people and animals wouldn't have food.