How Do you attach FPS arms to a Character controller, and create various animations for them within Unity?

Hello. I bought some FPS arms from the Asset store. In fact i got several different ones. My Question is how do you attach the arms to the first person character controller. And Two, how do you create animations for the arms within Unity Itself? And how would you execute those animations through scripting? I believe most FPS arms are poseable. In fact the FPS arms product page of my purchased fps arms states they are poseable. So if they're poseable, then it means i can animate them in Unity 5 right? I'm new to Unity 5. But i used Unity 3 and 4 alittle some years ago and i remember it had a Keyframing thing to create animation. So i assume Unity 5 also has that.