[M19] Suffering from insane dandruff

I'm suffering from dandruff since a long time but in last 2 years, it's getting worse. In winters, due to dryness...my scalp gets white showing the dandruff all over. Whenever i rubs my hand on hair, dandruff recklessly falls down. After taking a bath, my skin becomes whitish and same goes for scalp as well.

Please tell me how to fix this