We need more information than that to really help you come up with a solution. There are many different ways of doing this and a lot depends on how your game is currently created and what you want the outcome to be.
From your first post we get that it shoots when you drag. But answering each of aidians questions will really help get you the best answer.
Try to be as detailed as possible since we are not seeing your project or in your brain to know what you’re trying to accomplish :).