Start out by reading the Read Me threads at the top of the c++ forum. Especially the FAQ and Books threads.

Then google for c++ tutorials. Best to buy and study books, but if you can't afford them then read tutorials.

>>And my dream is to take over the operating system industry and make every people like my operating system!
LOL. So you want to put Bill Gates out of business???

My advice would be to get an introductory level book. Then download code::blocks (an application that helps you write programs) and start working on code. Do the exercises in the book you get and try to come up with your own interesting programs. In programming you definitely learn by doing.

Here is a Jump start:
Download and install (Check the one bundled with Mingw)
www.codeblocks.org

Books:
Thinking in C++
http://www.google.co.tz/search?hl=sw...meta=&aq=f&oq=

tutorials:
www.cplusplus.com
www.cprogramming.com

Happy coding!
Wait to see your OS

try to search in GOOGLE.COM so many tutorials available there...

>And my dream is to take over the operating system industry and make every people like my operating system!
ROFLMAO! The best I've heard in a while

The typical beginner's thought is back again!!
Well, see you back within a couple of centuries then?

>I'm 12 XD I want to learn about everything on computers.
Good luck then!
Really learning everything about computers is just IMPOSSIBLE, same as writing your own OS (and taking over the whole OS market).
You can learn much (very much) about computers, but I know no one who does really know everything about computers.
(But maybe you'll be the exception )

Thank you all for your great commentos.

... and not to forget: http://www.daniweb.com/forums/thread78223.html