The KM3NeT/ORCA experiment is a next-generation neutrino telescope, currently under construction in the Mediterranean Sea. The final detector geometry will reach an active volume corresponding to 7 Mtons of seawater, optimized to neutrino oscillation physics in the [1, 100] GeV energy range. In this way, the experiment is expected to reach a maximum sensitivity in the measurement of the neutrino mass ordering (NMO) by studying the oscillations of the atmospheric neutrino flux passing through the Earth.
Thanks to the detector's modular structure that allows for collecting data in stable conditions also with a partially instrumented volume, the first neutrino oscillation analysis has been already delivered with only 6 detection units (KM3NeT/ORCA6) and 354.6 days of stable data taking. In this contribution, KM3NeT/ORCA's sensitivity to the GeV neutrino oscillation physics, NMO measurement, and tau appearance will be presented. Furthermore, the first results from the KM3NeT/ORCA6 detector performance and updated measurement of neutrino oscillation parameters, with almost two years of data taking, will be reported.