Why does skin turn red when you place an icepack it? same with fingers why do hands turn red when put bare hands in cold snow for a minute ?

Ice pack: When the skin is exposed to extremes of temperature, normally there will be increased blood supply to skin. Hope I answered the question.

Vasodilation : Your blood vessels respond to a cold stimulus by attempting to warm the area reflexly - this is done by dilating, which increases blood flow to the area and causes redness and warmness.