There is a rest house for truckers that will serve a hardy dinner, its cheap but don't go expecting it to be pristine clean.
The people who live in Karakul are primarily ethnic Kyrgyz. No one speaks English here, so basic Russian or Kyrgyz is advisable.
There is a tiny shop which sells extremely basic products. They do not sell bottled water so if you don't like tea, make sure you bring something to purify your water.
Tea - every household will make tea as their primary source of hydration.
You might find some bottled juices or other drinks at the shop, but don't expect much.