I have small bumps around only my ring finger (mostly the back of my finger). they are itchy and some appear as a pack in several spots of my finger.

Dermatitis: Sounds like dermatitis. You may have an allergy to one of the metals in your ring (often it's to nickel, which is in many metals used for inexpensive jewellery). Or it could be irritation from water sitting under the ring after washing hands. Remove your ring until the spots heal. You can use mild hydrocortisone cream 2x/day for up to 2 weeks. Dry the skin completely after washing your hands.

Itchy bumps : These could be allergic rash or could be scabies . Scabies is causes by a bug which is transmitted by contact and is very contagious and so important to treat it at the earliest. Please consult a doctor immediately.