Both
yep
Skinks eat other skinks. Big Skinks eat the skinks that are smaller then the bigger skinks. They drink milk from cows as well. There main thing they eat is snails. How skinks catch snails: They first jump on the snail and stomp ot it to make it crushed. (they prefer snails crushed)
Ladybugs and cockroaches are in the same family (insects) but not the same Genus due to their obvious differences.
Australian skinks have a varied diet. Some of the things the skinks eat are moths, flies, caterpillars, and small insects.
Birds, frogs, toads, and some insects such as beetles and spiders are known to eat earwigs. Additionally, some small mammals like shrews and rodents may also prey on earwigs.
yes
Skinks can indeed eat banana skins. Though this is a possibility it is not very likely that a skink will eat a banana skin.
yes
they eat the plant stems
what does the cockroach eat
Yes, geckos do eat cockroaches as part of their diet.
Yes, cockroaches will eat an onion. The cockroach will feeds on almost anything that is left out on a counter.