Do i have to give my baby one year 3 months old vitamin d as he is not exposing to sun every day?

Yes: Usually all the children over 6 months gets multi Vitamin with fluoride , which contains vitamin D , he does not need separate Vitamin D. We only give vitamin D alone to babies under 6 months , who are born during winter months and breast feeding , older children may need separate Vitamin D if they are diagnosed with low vitamin D .

Vitamin D: Probably not necessary but it won't hurt to give one dose a week of 500 mg, As he gets older you can gradually increase the dose by day.