The food web is, let's say a chain.It's like, A worm(decomposer) breaks down dead animals and then turns it into soil, and makes it richer, let's say a carrot(plant) takes the nutrients in the soil to make the carrot grow, A rabbit (herbivore) comes and eats the carrot to make it live and grow. then a Hyena(Carnivore) ease the rabbit and the Hyena dies and so on and so on.
-This info does not contain Omnivores witch eat meat and plants.
Carnivores - eat meat only
Herbivores - Eat plants only
Plants - use soil to grow.
decomposers - break down most items into soil.