Beetles and weevils both belong to Coleoptera.

Some beetles eat other insects whereas other beetles may eat plant material.

It is by no means true that all beetles are carnivorous. There are beetle species that feed on roots, buds, leaf tissue, fruits and veggies, bark, wood, seeds, pollen, and every other part of plants. There are also beetles that feed on dung, and the remains of once living creatures.

Weevils are considered to be a type of beetle.

There are as many food sources for beetles as there are species of beetles. According to my "Field Guide to Beetles of North America" there are about 300,000 species of beetles in the world and other sources tell me that only about 10 percent of them are considered pests. A web search for "Beetles of Brazil" did not return anything except more "Beetles of North America". You may have better results.