**** I am not a teacher ****
"Confiscate" is correct. If you carry contraband items, the customs officer will confiscate them. He will confiscate or seize them, and you stand to forfeit them.
If you look at example sentences for both these words, the difference will become clear. For example, If you don't make the balance payment on time, you may forfeit (lose) your deposit.
Student or Learner