Hi You seem to be having male pattern hair loss. Dandruff or seborrheic dermatitis is an associated condition which increases the hair loss. Please use a mild anti dandruff shampoo and topical serums that can  be prescribed by your dermatologist. However remember that this hair loss is progressive in  nature and you have to be consistent with following the medicines as advised yo get the results. Make sure your diet contains lots of fruits and vegetables and protein. quit smoking and do exercise at least 5 days a week. Do consult a dermatologist to get a customised treatment plan