hello and welcome to health care magic, I am sorry that your brother feels unwell.
There are different possible causes for what you are descirbing. It could be a fungal infection
of the scalp
, these would usually start as dry scaly circular patches or in some instance thick boggy swelling in the scalp. They are usually associated with hair loss and itching. Sometimes as result of itching the area you may get a baterial infection along with the fungal infection which would then cause the pus. Fungal infections are contagious and would require a doctor to see him and confirm it by history, examiniation and in some cases investigation of the hair. It is treated with a course of oral antifungal
which need to be taken for a few weeks.
Another possible cause is baterial infection of the hair follicle. It may just involve the hair follicle in which case it is called folliculitis
or it may extend a little deeper and is then called furunculosis
These would cause pus to be discharged and you may have more than one. In some people they may heal and return. The usual treatment involves hygiene (cleaning the area repeatedly, washing hands after and discarding material used), applying warm moist compresses to encourage draining ( after drainage
can still use compresses). Antibacterial soap may prevent spread.
I think that it is likely to be a boil and though these are usually managed at home, in light of your brother's age and the fact that he has a fever, he should be taken to see a doctor for examination and treatment.
I hope that he feels better.