Create and implement a domain rewrite rule on an NGINX server

I have a web application running on a Digital Ocean Droplet running an NGINX server. Two domains are configured for the server, although currently the web application is running just on [[login to view URL]]. All URLs on [[login to view URL]] resolve to the root of the web-application. I’d like rewrite rules set up for NGINX so that all URLs in the format [login to view URL][xxxxx] (and https) are directed to (with original URL staying in browser address bar), to [login to view URL][xxxxx]; where [xxxxx] is a 5 character Alpahumeric code. I’m looking for someone with a lot of NGINX config experience and, ideally, familiar with Digital Ocean