Calculating angle from camera to object

Hi, so Im designing a robotic arm project, Basically, my camera will be raised to about 10 cm above the table, I want to calculate the angle from the camera to object, but not sure how to go about this. Picture below shows an example.

[Benjamin Thompson]

How are you using MATLAB to solve this problem? If you use the camera calibration tool in the Computer Vision Toolbox, you could track your object within a known plane, and the positions that you get after applying camera calibrations may help solve your problem.

https://www.mathworks.com/help/vision/ug/camera-calibration.html?s_tid=srchtitle_camera%20calibration_3

If you have more specific questions after starting on your problem please post them.