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The role of feedback in the self-regulation of star formation is a major problem in astrophysics. Stellar feedback is the sum of all the processes by which massive stars inject energy, momentum, and mass into the ISM. For the first time, the velocity-resolved SOFIA [CII] line observations enable us to quantify the relative importance of pre-stellar and main sequence stellar feedback. We examine stellar feedback mechanisms during the protostellar phase through jets and outflows and during the main sequence phase feedback via stellar winds. Recent [CII] 158 μm observations of the Orion Nebula from the SOFIA C+ SQUAD Large Program revealed an expanding bubble, the Veil shell, being powered by the stellar winds of θ1 Ori C, the most ionizing star in the Orion Nebula. By examining channel maps and position-velocity (PV) diagrams spanning the entire Veil shell, we identify [C II]-emitting cavities at different velocities ranging from 1-2 km/s to 15 km/s relative to the Veil shell. We find that these cavities were created together by the fossil protostellar outflow of θ1 Ori C and by active outflow from less-massive stars, especially B-type stars. The momentum deposited during prestellar feedback is about 10% of the momentum that the Veil shell has, deposited through stellar winds from the Trapezium cluster. Moreover, by creating cavities, these fossil shells may already have broken the Veil shell, and outflows from less massive stars may have made the Veil shell porous.