Hi welcome to Health care magic forum. It is an
abscess formed as sebacious
cyst, as it ruptures little pus oozes out, leaving behind the pus pocket, which is to be liquified and come out. For that medicines are to be used under the supervision of a doctor. Surgeon is the doctor concerned but no problem who ever it may be.
Besides i advise you some diet recommendations as avoid taking pulses, potato , other tubers, and fish.
Take more of green leafy vegetables, milk, meat, fruits, juices, and dry fruits, to improve blood, general health, resistance to such infections. Wishing for a quick recovery and thanks for calling.