S is homesick at college. A says that it takes some time to get over homesickness. (She didn't use this expression, but that's what she means). S decides that since it takes some time, she will give it some more time. She will give it one more year, to see if she gets over her homesickness. That is, she makes a commitment to stay at college for one more year before she decides whether she should quit or not.
"It" = "the process of getting over homesickness".
Student or Learner