깐 is an attributive adjective form of 까다.
까다 can mean 1. to peel (the skin of fruit, etc). 2. to bare something by removing covering. 3. to hit/punch,
For opening a can, we use 따다 (open by breaking the seal) more often, as in 깡통을 따다, 딴 깡통 (an opened can).
깐 is sometimes used, but it sounds a little slangy.