The T2K neutrino experiment in Japan obtained a first indication of CP violation in neutrino oscillations. To obtain better sensitivity, T2K upgraded the near detector. A novel 3D highly granular scintillator detector called SuperFGD of a mass of about 2 tons will be functioning as a fully-active neutrino target and a 4$\pi$ detector of charged particles from neutrino interactions. It consists of about two millions of 1~cm$^3$ optically-isolated plastic scintillator cubes. Each cube is read out in three orthogonal directions with wave-length shifting fibers coupled to compact photosensors, micro pixel photon counters (MPPCs). SuperFGD was installed into the ND280 magnet and exposed to the neutrino beam since October 2023. In this presentation, the main detector parameters, detection of first neutrino events, and its performance in the neutrino beam are described.