I do not think you will get anyone here to help you write a backdoor, well, not openly at least

You do not explain your reasons, and even if you did, I wonder if people would really believe you.

I do hope you read the front page of this forum.............carefully?

I would point out that those who do not KNOW how to write malware get caught........for certain.

I agree with SirDice....................learn assembler, and then you will know

Take care, I think that you might need to?