A good place to start looking for information can be:
OSDev[
^]
Their
set of tutorials[
^] help you cover a lot of ground towards building your own kernel once you've understood the fundamentals.
There are many things you need to do to get something like Windows, Linux, MAC OS, etc.
I'd suggest starting off with trying to build a bootable kernel and then continue with i/o interfacing, memory management, maybe a file system, a shell and networking (I'm sure I missed a lot of things but these should be a start).