NDIS filter driver : modifying packets

Hi, I’m the new one starting to develop filter driver .
My English skill isn’t good so please excuse me :wink:
Because it’s my first time about it, I could not know how do I start. I didn’t have any opportunities for learning it before.
Anyway, I want to modify packets for changing the destination of the packet and make it to reach to another IP, and vice versa.
I read so many msdn documents, now I know that I should write FilterSendNetBufferLists function and make clone about NBL for modifying it.
However, hopelessly, I couldn’t get any details that implementing these things…
Please give me some hints how can I modify packets and where exactly I should write these things in filter driver sample?

Really thanks,