"The Metamorphosis" is the usual short story appetizer (often assigned in high school). "The Trial" is typically the introductory novel, though if you want to b

"The Metamorphosis" is the usual short story appetizer (often assigned in high school). "The Trial" is typically the introductory novel, though if you want to be a rebel you could start with "Amerika" instead. "The Castle" is the best novel but probably too difficult to start with unless you're already well-read.