Hi! Akshay kumar,
Welcome to HealthcareMagic forum,

The most common cause of hair loss in men is ANDROGENETIC ALOPECIA(MALE PATTERN BALDNESS).Other causes are iron deficiency, hormonal, thyroid problem, stress, lack of sleep, familial etc. Other rare causes are zn & copper def. One has to find the exact cause of hair loss and treat.
You can start with topical preparations like Minoxidil sol 5% applied twice daily on scalp. Take tab biotin one daily. Since you are above 18ys you can also take tab finestride once daily for couple of months. But you need to consult a dermatologist for all this .You need to continue the medicines for long to have good result.But then if you have male pattern hair loss then the result would be temporary .Medicines would give you result for 3-4 yrs ,then again you would start loosing hair if your familial pattern is so.
Improve your diet with green leafy veg, fresh fruits, plenty of water, pulses, high protein diet, avoid items with high sugar content like sweets & chocolates, less of Chinese foods, less of pizza & burgers ,more of milk & ghee, dry fruits . Good sleep also has a important role to play .

We at apollo hospital have lasers also like HAIR MAX LASER ,to stop hair loss and help growing of hair.We also do MESOTHERAPY to reduce hair loss.You can visit our website www.skinhairclinic.com or www.apollobsr.com (dermatology section).

The only permanent solution to baldness is hair transplantation ,but then you are too young for that right now.We do hair transplantation for those needed at apollo bsr hospital ,bhilai.

I hope I've answered your query ,if you have any follow up question ,kindly write back to us.
regards,
Dr.Chawda