How to stretch the lens of 3dmax camera?

I don't know if you're asking about the lens change caused by installing a camera.

About the following changes can be reset.

1. Adjust the focus in those viewing tools in the lower right corner, and so on.

2. Cut a parallel view (others in the upper left corner can do all these views), and then press the P key to switch back to the perspective view.

3. Create the default camera, then cut to the camera view, and then delete the camera.

4. Adjust the camera parameters, the standard is 65.