How to set up a camera to track and shoot birds flying in 3DMAX?

in this case, you should use a Free Camera.

for example, for example, the third-person angle of view that follows the car like Need for Speed Car, first create an auxiliary object (Dummy1), and then move it to a position a little above the back of the car. Link it to the car object. Then create a free camera, move to the vicinity of dummy1 in the initial frame, adjust the camera FOV and other parameters, rotate it to make it pan a little, and adjust the field of view to the effect you want. Then link the free camera to the auxiliary object dummy1. At this time, the animation is played, and the camera view is the following shot.

Of course, it is also possible to link the free camera directly to the car object, but in this way, the car in the photographed picture is fixed and there is no movement. After linking to dummy1, you can also play some rotation key frames for the free camera in the adaptive position, so that the car that follows the shot looks full of movement. Other focal length changes and so on, where do you want to adjust, just set the key frame animation.