Take a look at the MKS-DLC32 board. It's a (documented, but poorly!) ESP32-based 3-axis 3D printer controller board. It runs grbl on one core so it can understand g-code, and it has a local UI with web and BLE connectivity on another core. The source code is on github, although it takes a bit of digging to find it (that poorly documented part!).

I don't know how complex your Windows code is, but it's an interesting architecture to study. I bought one of the boards (they're all over Amazon) since it had everything I needed for a motion-control project, but I ended up with a simpler solution.