There's nothing built-in in Rust for this. You will have to use Apple's macOS-specific APIs. You will need to use ObjC Cocoa APIs. There are higher-level bindings for some core macOS APIs, but I don't think anyone has made higher-level wrappers for windowing yet, so you will be on your own.
To be honest, if all you need is to manipulate macOS windows, then you're better off using Swift.