An internship is a role where a person learns how to do this. (And someone who knows how to do this knows it’s orders of magnitude more involved than the two days you were given — two months is a more realistic timeframe.)
Here’s a personal experience of mine, so you have more to compare this with:
When interviewing for a developer position (not an internship), I was once given a take-home programming task to complete over 2-3 days: basically a small, self-contained web app that they had made intentionally buggy and poorly-composed in various ways. I was tasked with identifying & fixing the problems, then providing a write-up of why I changed what I changed. (The package was different enough from their specialty that it was pretty obvious I wasn’t doing their work for them. I confirmed after being hired that this same task was given to all applicants.)
Again, that was for hiring a developer. The whole point of an internship is that you’re being taught and trained on the job.
If you’re already able to build what those people asked of you, then you’re overqualified for the role.
Im pretty sure I saw this as a visual gag in a Muppet Babies comic book in the 80s! I think it was issue #13… I might still have it packed away somewhere