Hi. You may be suffering from early onset androgenetic alopecia. Does your father or brother or maternal uncles have balding? This could genetically predispose you to balding. Further environmental factors , pollution, stress, junk food and poor diet could cause you to lose hair further. You'll probably need treatment with hair care lotions or serums - something that has vasodilator properties and improves thickness of hair and reduces hair loss. Have a good balanced nutritious diet. Yes your hair density can be restored if you take timely treatment and care of your hair. For dandruff you'll need an antifungal shampoo. Seborrhoeic dermatitis is a chronic problem in most individuals.See a qualified dermatologist near you. Hope this helps. Let me know on follow up messaging if u have any further queries. Warm regards.