Compiling linux kernel from source with external module

So, actually I am using raspberry pi with OS version Stretch and kernel version 4.14.98-v7+.

I need to add kernel module for wifi module I use from this repo:

While on it, I check that it is supporting 4.19 kernel. I am thinking to download the linux source for 4.19 kernel from this :

I have read that I can build my own kernel:

Is there a way to compile the kernel source including the external module?