Hello..Thanks for your query
You seem to be having folliculitis
of the scalp
.it my be of bacterial or fungal origin. In most cases the cause id the bacteria Sthaphylococcus aureus.
You will need a course of systemic antibiotics to cure this.
You can use Betadine
lotion as shampoo twice weekly.This will held in case your folliculitis is due to bacteria also help in the crusts and keep the scalp clear.
Hope this is helpful.