Interferometric polarization observations have found that, at cores scales, magnetic fields play an important role during the star formation process. However, their relative significance in their environment and their role in stellar multiplicity remains poorly understood. BOPS has observed 870 um dust polarization toward 57 young protostars in the Orion molecular cloud, which is considered to be a typical representation of star-forming conditions within the Galaxy, on scales of 400 to 2000 au. At these scales, the observations uniformly probe the magnetic field structure in envelopes around the protostars. We also map the CO(3-2) outflows and the C17O(3-2) core's kinematic to better understand the role of angular momentun in the star formation process. Combined with ancillary data, we investigate the origin of stellar multiplicity and understand the role of magnetic fields during the star-forming process.