Mostly aphids
Most lady beetles (known as ladybirds in UK) are beneficial as both adults and larvae, feeding primarily on aphids. They also feed on mites, small insects, and insect eggs. aphids
What kind of grammer is this? You sound like a retard. It should ask, "What do beetles eat?" Idiot, you are.
mice and other insectivores eat beetles.
You do not eat a beatle.