Advice
In the first couple days, you wont have much to do until you get set-up with all the needed permissions. Take this as an opportunity to research the technologies your team uses, any team documentation or source code, and generally what you will be doing for the summer. You get out of this sort of company what you put in. If you find that there's not enough work, ask your boss/team for more opportunities, or make your own opportunities by starting a project with other interns and the recruiting office.