Graphite acts as a structural material for the interior of the reactor, and also acts as a moderator of fast neutrons so that the nuclear reaction takes place in a controlled and safe manner. If you do not use graphite rods in the reactor, then the nuclear reaction will begin to develop rapidly, and an atomic explosion will occur at the power plant, which will be a disaster. Therefore, moderators are used so that the entire volume of nuclear fuel is divided gradually and thermal energy has time to be transferred to the coolant, and then to the electric generator.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.