Write your introduction for the student(s) who will complete the WebQuest. Students are your intended audience so you want to make this learner-centered by writing to the students.
The introduction sets the stage for the entire WebQuest - it should spark interest and make clear what students will complete by the end of the project. Take some time and review Bernie Dodge's (who originated WebQuests) WebQuest Taskonomy to get ideas for how you can frame your quest.
The introduction should include: