Calcium builds bone structure. Vitamin D is required for calcium absorption from the gut. Without adequate vitamin D, you can consume plenty of calcium and still have poor bone health. Dairy, fortified plant milks, ragi, and sesame seeds are good food sources of calcium.
Vitamin D insufficiency is widespread in India despite abundant sunlight, primarily because of limited sun exposure and indoor lifestyles. A daily supplement of 1000 to 2000 IU of vitamin D3 is reasonable for adults with limited sun exposure, with testing to confirm adequacy.