hey everyone....
am interested in kernel programming....
can anyone tel me how do i start???
wat language i use and some of the things i need to already knw!!!!!

also something about GUI programming..

step one) Learn to actually type out words.

As for language, it will be a combination of C and inline assembly, actually, you can also use C++ or any other compiled language in place of C, but Linux is programed in C (i assume thats what you ment). You cant escape the assembly however, the boot phase of any kernel requires that it be done in assembly, because you need to setup the CPU, a task that cant be done by using C. The design of the kernel is what will determine what general purpose language you will use, some kernels do use C++ or other languages, but they are a minority, mostly created for research.

For GUI programing, look at GTK or QT, is that what you ment?

Easiest way into kernel programming is to learn to write a kernel device driver. These can be installed as modules in a running kernel, which greatly facilitates debugging.

Try this book:
www.kroah.com/lkn/