How can i treat boils/abcess on my bum, in between my legs/groin area, under my breasts and under arms?

See Dermatologist: For a single boil, you can do sitz baths where you soak in the bath tub for 10 minutes 1-2x/day and this usually helps. However, what you are describing sounds like hidradenitis suppurativa. See http://mayocl.In/pyza6t . I would recommend that you see a dermatologist for treatment as you may need antibiotics and/or other treatments.