Haven’t you read all the links posted by @skieurope ? You’re asking the same question over and over. There’s no point ever in emailing to tell Harvard why you want to attend. You convey that in your essays and SHOW them how you are a good fit.
Maybe you can submit artwork (highly doubt it), but you need to look at what they say about that. Some schools will only consider artwork that is juried, and it probably has to be submitted via a separate portal. But think hard about that. If your artwork was good enough to submit, they might wonder why you didn’t do so when you were supposed to, like other applicants who submitted it on time. How will it reflect favorably on you that you’re only just submitting it?
And fwiw, you sound very much like a former CC user who lived in the UK, submitted an hour before the deadline, and also interviewed with Stanford (or was that your “friend”?)