Hello
As you are nineteen and as your puberty as hit you long back, I suspect your hair loss would be genetical or stress related. Plus as you said dandruff, i feel you are much exposed to pollution and have a dry skin.
So ideally we are talking about androgenetic alopecia and dandruff as a whole.
Next Steps
you need to start with anti hair fall medicines like some sprays and multivitamins.. also prp therapy would work well with you. you can contact us for the medicines to be taken at home as we provide delivery services as well.