Please elaborate on how much vitamin d is effective to treat covid-19? may sunlight be a vital source considered for this?

Not a treatment: Many patients who are ill and hospitalized with COVID 19, may have Vit D deficiency. The dose of Vit D depends on your age and requirements, and baseline level. In general at your age 1000 IU supplements daily and a healthy diet may be sufficient.

COVID 19: Vitamin D is not a specific treatment for COVID 19. However, if Vitamin D deficient - that needs to be corrected with supplementation. Dose to be determined by provider.