Hi Thanks for your query. You could be having some severe form of dandruff. Use a good antidandruff shampoo and apply clotrimazole cream twice a day.
Health Tips
Following healthfeeds should be helpful
"What Makes Your Skin Prone to Acne? Top 5 Causes of Acne" by Dr. Jolly Shah Kapadia - https://www.practo.com/healthfeed/what-makes-your-skin-prone-to-acne-top-5-causes-of-acne-14523/post
"Teen Acne: What Helps, What Hurts!" by Dr. Jolly Shah Kapadia - https://www.practo.com/healthfeed/teen-acne-what-helps-what-hurts-14525/post