How to make text border go outside of text and not inside

The only way around this I've found, is once you've finished making your text, convert it to a path.  That way you can add a border to it.  It's a good idea to copy the text first so you've got a backup!

XD can't do that, but Figma can (which Adobe has announced their intent to purchase, although that has not yet been finalized). XD is a dead-end product at this point, so I'd recommend switching to Figma (which can do that you want).