Cross-compiling a kernel module

I’m working with a Jetson Orin Nano and I would like to use a kernel module that is not available in Jetson Linux r36.5. I would like to build it from the sources, preferably with cross-compilation. I’m finding the manual a bit hard to follow, though: Kernel Customization — NVIDIA Jetson Linux Developer Guide

Where can I find this source_sync.sh script? Is it something I can just run stand-alone or does it need to be ran inside a file tree?

Where is the git repo?

What exactly should I download from Jetson Linux Release 36.5 | NVIDIA Developer ? The BSP, the root filesystem or both?

I also see that in Jetson Download Center | NVIDIA Developer maybe 36.5 is not available yet? And is it really the “driver package” that I should get? Pardon if I find the name a bit confusing.

To clarify, I’m only trying to build a “in-tree” module, hopefully the simplest of kernel-related tasks, I appreciate any help. I tried to follow instructions on the PC (with cross compilation), and now on the Jetson itself. I believe I have the source code, but how do I obtain the “.config”? The documentation says “follow those steps to get the `.config`” but it doesn’t seem effective. Can I just use `/proc/config.gz`?

The source_sync.sh can get by sdkmanager.

If you are using sdkmanager to flash the device. It should generate and save in the host.

And you can download the source from below link.