How would go about making gun follow cursor?

There are plenty out there for r6, but how do I make it for r15, a big example is jailbreak. When you point the cursor at someone, and you see the gun pointing at someone, that's what I want to be able to learn to do. Time ago, I wanted to make a r6 gun that has CFrame animation, a helper said, changing the CFrame animation is painful, most of the cursor followers contain CFrame so I'm not sure if that's a problem. But I just want to learn how to do it. Thnks