I have attached a sample for you. This is majing use of only 1 camera. I f you need more than one, just replicate the camera code and add more picture boxes. Please note that the codes is NOT commented, but most should be self explanotory if you have a basic idea of API's etc.
Amit, I have already overstepped the basic rules of this forum for supplying you with sample code, without you doing anything. The code example I gave you is only for reference to help you getting started. I will and can however not design your application for you without getting paid. You need to show the community what you have already done from your side, that is where we as the helpers come in, we will help you with error code, design etc.
If I look at your question above, I do think that the sample code covers what you need, you need to develop it further from here.
I think you must go through the Rules and Regulation of Posting. Here helpers don't give full developed source code without seeing what you have done.
I think AndreRet's help is more than enough for you to replicate code so that you can handle more than one webcam.