Student or Learner
1) The land is use for growing what kind of crops?
2) What kind of crop are grown in this land/plot?
3) What is their purpose of breeding the chicken?
4) What is this chicken bred for?
3) and 4) do not sound natural. Nobody breeds a single chicken.
Consider these suggested improvements:
3) Why do they breed chickens?
4) What are these chickens bred for?