Hair loss from low Vitamin D or genes?

Now I am 18 male and from the last 5 years I am losing hair that’s why the front portion of my hair had become so thin that one could easily see my scalp, 2 months ago I came to know that I have vit D3 deficiency it was 11.78 ng/ml, now I am under treatment so anyone can tell me how much time it will take to regrow my hair?

If you Vitamin D levels are low and this is the cause of your hair loss, you can expect to see hair regrowth in a year or less; however, as a male, then the loss is most likely genetic (99% probability),  Time will tell?