do you know what is a atom in science

An atom is a combination of particles (such as electrons, protons, and neutrons) that form a basic building block in chemicals. They are the source of nuclear energy (when they tear or fuse) and every atom has its own element. They can emit radiation if they are unstable and has an antimatter opposite (positrons, antiproton, and if antineutron is a thing).

Atoms are the basic units of matter and the defining structure of elements