Here is a detailed description of the video: The video shows a person preparing a mixture in a bucket. The person scoops a white powder from a brown paper bag labeled "гипс c..." (gypsum c...) with a white plastic scoop and adds it to a bucket containing a milky white liquid. The background shows a white tiled floor, a white window sill, and a wooden panel. The person's foot is also visible in the initial frame. The overall impression is that someone is mixing a type of plaster or similar material for construction or repair work.