So I don't believe that Vitamin D prevents COVID but I still increased my intake of Vitamin D because it seems like Vitamin D deficiency increased the severity of COVID. I wear a mask and practice social distancing to prevent COVID.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7385774/ is a UK study from July that doesn't come to any conclusions but they say "Our opinion is that if vitamin D does in fact reduce the severity of COVID-19 with regard to pneumonia/ARDS, inflammation, inflammatory cytokines, and thrombosis, then supplements would offer a relatively easy option to decrease the impact of the pandemic."