DarkComet RAT is a well knows RAT (Remote Administration Tool) th at allows you to simply control anyone's PC by simply forcing them to download a fake program with a virus in it. It gives you a lot of abilities. You can do really awesome things. There are other RATs that allows you to do more. But they are for professional's. No offense, You just need more knowledge for them. But this.. It really simple. You will plant the Trojan in ANY .exe file and Upload it to any link. Once anyone downloads you will be able to control ;D. Here and ONLY we're offering you Awesome Stuff.
PS :- If you need help i recommend you to check YouTube Tutorials. :)