How to get familiar with a system

[by]

Hi,

Yes, i have installed the FreeBSD 10 RELEASE on my i386 machine(a laptop).

And i know it needs long time to uncover the secret of an operating 
system, and this is my long term aim.
So i do not know what can i do in this long period of time, i mean i 
must do some projects with deadline, and i know i must make a deadline 
by myself, or i will be buried by the details, never out.
And i think the scheduler and interrupt handler are two of the basic 
things i must know if i indeed want to hack the operating system.

-by