Adjust FOV when locking on

Hi, fellow creators!
Is it possible to know if your camera isn’t showing your whole character on screen and if so, increase temporarily the FOV to make it fit in?

Knowing if the whole character is on screen no, but you SHOULD be able to check the distance from the camera to the actor and adjust either FOV or Spring Arm Length to suit it; it’ll just require some guess and check to get right, especially if the viewport is of variable size.

The problem here is: Let’s put for example that you lock on an aerial enemy or a very big one? The camera will try to point towards that direction, but that might leave your actually controlled character out of the screen. So I thought, increasing the field of view would solve that. But in order to do that I would need to get the rotation angle and define when the angle is steep enough for me to apply a FOV or camera distance increase? Is there a way to get the rotation angle from a rotator? If so, is the angle in degrees or radians?