Hi!
Vitamin D supplements are available as OTC medication, but the dosage depends on your current vitamin D levels. Please do a blood test to check your current levels , and only then you can take supplements with a valid prescription.
Include milk, ghee, nuts, flax seeds and eggs as a good source of vitamin D, try to get 10 minutes in the sun- preferably before 11 am in the morning.
Next Steps
Consult on practo.com for further advice
Health Tips
Avoid taking any medication or supplement without expert advice or prescription