Błędnie: My sister and her boyfriend have been preparing for the trip. They have bought some instant food and conserves- fish and meat. Poprawnie: My sister and her boyfriend have been preparing for the trip. They have bought some instant food and tinned food - fish and meat.
"Conserve" to rodzaj dżemu, kofitury. Żywność w puszkach (konserwach) to natomiast tinned/ canned food.