tufailabbas949-spec/backend-mern ? reverse-engineered prompt

I want a simple backend for a MERN style app that I can run locally and understand easily. Please build it so it has a working server, connects to a database, and includes a few basic API endpoints for creating, reading, updating, and deleting records, something like posts or users.

Keep the code clean and easy to follow, with clear setup instructions and sensible folder structure. If it makes sense, you can organize it into a few small example app folders since this repo looks like it may be for practice or multiple projects. Please include basic error handling, environment based config, and a few sample requests so I can test it right away.

If you need to look up current docs online while building it, go ahead.