Hi wasim,
I suggest you start by reading _many_ datasheets, application notes, etc. about this topic first.
Then, when you have learned to program a µC, send data via RS-232 and write code for both
your PC and your µC, you will realize how much you gained from your studies in that you are
able to solve further problems on your own and will probably look back smiling to this request
for help. I do not mean to be rude, but try to make you first do some research and then ask
for details; NOT ask for the finished product and unlimited support for free.
Best regards,
dpenelob
P.S.: A good starting point may be
this blog.