hi..thanks for the query.
There are two most common possibilities:
1) Boils:A boil is a skin infection
that starts in a hair follicle or oil gland.Most boils are caused by a bacteria.people more susceptible to skin infections:Diabetes,Problems with the immune system,Poor nutrition,Poor hygiene.You may apply topical antibiotic
creams like Mupirocin
twice daily on the lesions.
2) Keratosis Pilaris: this is a common skin condition in which keratin forms hard plugs within hair follicles.it is harmless.It is more common in people who have dry skin.Treatment may include:Moisturizing lotions to soothe the skin and help it look better.Skin creams that contain urea/ salicylic acid/tretinoin
You can consult a dermatologist
for finding out the exact diagnosis.
Hop this helps .Take care!