Tracking and focusing are two entirely different concepts, but they are joined at the hip.

Focusing is pretty straight forward.  In One Shot AF mode, you put the enabled AF point on the subject, half press the shutter, and the camera should lock focus and beep.  In AI Servo AF mode, the camera focuses, but it does not lock until you fully press the shutter button.  AI Servo AF mode is designed to allow the camera to stay focused on a subject, whose distance to the camera is constantly changing.

You the photographer are primarily responsible for tracking your subject, which means keeping the AF point on the subject as they move.  This often omes into play during sports and wildlife photography shoots.  You must move the camera to not only keep the subject in the viewfinder, but also covered by the active AF point.

In AF Tracking modes, the camera can automatically reselect AF points as your subject moves around the viewfinder.  This is a more advanced mode of using the camera.  The user must go into the menus and tell the camera which AF point to use as the initial AF Tracking point,

https://community.usa.canon.com/t5/EOS-DSLR-Mirrorless-Cameras/What-s-the-difference-between-AF-Tracking-and-AI-Servo/m-p/325465#:~:text=In%20AI%20Servo%20AF%20mode,the%20camera%20is%20constantly%20changing.