In the video, a person is seen holding a knife and cutting an onion. The person starts by cutting the top of the onion, then proceeds to cut the sides of the onion. The onion is placed on a wooden cutting board, and the person cuts it with precision. The knife used is a chef's knife, and the person's hands are steady as they cut the onion. The onion is a medium-sized, brown onion with a white interior. The person cuts the onion into even slices, and the video ends with the onion being cut into several pieces.