You can add a border in a Google Docs page using a workaround, since there's no built-in border tool for doing this automatically.

How an attractive cover page can be added? You can find pre-formatted template and write on them and Google Docs has a lot of templates to make the cover page a really attractive one.

Google Docs lets you add headers and footers to your documents and automatically insert elements like page numbers, page count and footnotes.