Subscribe button leads to 404- Page not found

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I just started a ghost site and I think I made a mistake by deleting the “ghost” staff because I fast wanted to delete the old posts. I’m not a hundred percent sure this is the root of the problem but if it is, is there a way to get the “ghost” staff back?
My problem is that when you click the subscribe button it goes to a 404- Page not found. I’m guessing it is because I don’t have a page called “newsletter” but even if I would create a site that’s called newsletter that wouldn’t have the sign-up form for subscribers on it. How do i do this?