You can run these days macOS as a virtual machine. I have some experience reverse engineering iMessage. Here I only needed to look into the network requests with some SSL pinning removal.
There are some decompiled libraries of Apple's libraries so it helps. Many tried to reverse engineer macOS/iOS before so there is a helpful amount of knowledge out.
I think the best way is just to open up a decompiler program and just start RE. The decompiled source code contains some metadata such as function names so it is readable.
You can run these days macOS as a virtual machine. I have some experience reverse engineering iMessage. Here I only needed to look into the network requests with some SSL pinning removal.
There are some decompiled libraries of Apple's libraries so it helps. Many tried to reverse engineer macOS/iOS before so there is a helpful amount of knowledge out.
I think the best way is just to open up a decompiler program and just start RE. The decompiled source code contains some metadata such as function names so it is readable.