I think that host gator doesn’t give you a full server, so you’d need to change hosting to do a subfolder install (actually, I think you might be able to a subfolder install with cloudflare in front, but I don’t know that anyone has done that).
Subfolder installs aren’t recommended and it seems that few people still believe that there is an SEO advantage, but if you want to do that, you’d see Subfolder support with Docker