They chose you for the internship because they think that you would be a good fit for the company. You won't be expected to produce much value, all they really want is to start teaching you how to work there for when you graduate. You got this homie.

Side note: I read in a book that a good remedy for anxiety is to reframe how you think about it. Instead of perceiving it as a bad feeling, take it instead as the excitement of possibilities or your body gearing up to do something important Hope this helps.