Which organism is a consumer?

The organisms that obtain their energy from other organisms are called consumers. All animals are consumers, and they eat other organisms. Fungi and many protists and bacteria are also consumers. But, whereas animals eat other organisms, fungi, protists, and bacteria "consume" organisms through different methods.

consumers have to feed on producers or other consumers to survive

Explanation:

they can be considered carnivores, omnivores or herbivores. In other words, primary, secondary or tertiary consumers. Deer are herbivores, which means they only eat plants (producer)