WHAT SHOULD I SAY FOR THIS POSITION I'm VOLUNTEERING FOR, PLEASE HELP.?

This is the email: This is wonderful. The City definitely has opportunities, but we want to make sure you get the most out of your volunteer experience. Could you send me a letter with details of your interests, skills, experience, and what you would like to gain from volunteering? We want to match you up with the department the best meets your needs. What kinds of Depts? Also what should I say on why I want to volunteer, and other stuff the email mentioned. I'm young and not sure on what to say. What if they don't like me? Or unqualified?