Hello,
From the symptoms this problem of dry itchy scalp can be due to dandruff or seborrheic dermatitis. You can treat flaking and dryness with over-the-counter
dandruff or
medicated shampoos.
Shampoo the hair vigorously and frequently (preferably daily). Active ingredients in these shampoos include salicylic acid, coal tar, zinc, resorcin, ketoconazole, or selenium.
If the symptoms persist, then it would be best to get it confirmed from a dermatologist. Eat a healthy diet.