Hi,
that's not a question. Sorry but we all have much to do and some life, so nobody here will do your work. If you have specified questions or problems, small corrections to your code you're welcome.
You should start with this:
http://msdn.microsoft.com/en-US/library/system.io.ports.serialport.aspx[
^]
In this Article there are all things you want to achieve (open port,read,write,loop) very well explained.
With Best Regards