I do not move and I absorb nutrients from dead materials

You might be referring to a type of organism known as a decomposer or a scavenger. These organisms, like fungi and certain bacteria, obtain their nutrients by breaking down and extracting them from dead organic matter such as dead plants or animals. They play a crucial role in the ecosystem by recycling and decomposing organic material, helping to break it down into simpler compounds that can be reabsorbed by other organisms.