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Recently comma the TESS spacecraft uncovered an exciting three-planet system that included its first habitable zone terrestrial planet comma TOI-700 d. This system orbits an M2V dwarf located 31 pc away from Earth. Previous studies of the TOI-700 system have not included photochemistry comma but photochemistry can strongly impact planetary atmospheric composition comma habitability comma and observable spectral features. A critical input for accurate photochemical modeling of this system is the UV spectrum of the host star comma TOI-700. Measured UV spectra of exoplanet host stars have been heavily used for a diverse range of modeling efforts and are a critical in-demand need of the exoplanet community. We will measure the UV spectrum of TOI-700 (1150-5000 A) comma use it to update previous modeling efforts of possible atmospheres and spectra of TOI-700 d comma and make the spectrum available to the community. This will result in the first self-consistent model atmospheres for TOI-700 d using a 3-D climate model with clouds and atmospheric dynamics coupled to a photochemical and spectral model. We will be able to put this new analysis into the context of previous works considering climatically and photochemically self-consistent atmospheres and spectra of potentially habitable M dwarf planets. TOI-700 will be the earliest M dwarf for which such a study has been performed for a specific known planet and will thus provide a useful point of comparison against potentially habitable worlds around later M dwarfs comma including TRAPPIST-1 (M8V). The stellar UV spectrum we measure will also be able to be used in future works considering the atmospheres and spectral features of all planets in the TOI-700 system.