Abstract: The NOvA experiment is a long-baseline neutrino oscillation experiment that measures electron neutrino appearance and muon neutrino disappearance using neutrinos from the NuMI Beam at Fermilab. These measurements help constrain important neutrino oscillation parameters, including the CP violating phase, atmospheric mass squared difference, and largest mixing angle. However, to make precise measurements, it is crucial to understand the background and the sources of systematic uncertainty to the appearance signal. The NOvA Near Detector (ND) data provides a high statistics probe into these uncertainties, including our limited understanding of neutron interactions, which is a key uncertainty for antineutrino measurements. I have developed techniques to identify neutron energy depositions and used them to estimate the associated uncertainty. The ND data also provide a probe into misidentified events that might mimic the signal at the Far Detector. I have also developed a method to obtain a data-driven correction to these background components to better estimate their impact at the Far Detector. This talk presents our current understanding of neutron interactions and a new method to estimate the background components for the neutrino oscillation spectrum.