add lines to kernel source

[mohamadaliakbari]

How can i add lines to appropriate files in kernel source and compiling
kernel, so that during extraction of zipped kernel image, it prints
hello world?

[dragoncity99]

Okay, I suggest you start from how to modify slightly more simple apps like C code apps  "Basic GNU utilities - i.e.: ls" --> "app server - i.e: apache" --> "kernel"