I want to mimic effects some YouTubers use where they track an object then zoom in on the object that is being tracked. An example would be someone's head moving in a frame, and it cuts to a close up that moves with them. So far I've got track points but I'm stuck from there. A video of what I would like to get is here:
I think you just need to break this into two steps. First, do the motion tracking and apply the tracking data to whatever. Render that out, or sub-comp it. Second, use AE (or just use your video editing software) to do the zoom-in where needed. There's not much benefit to doing it all in one pass, as far as I can see from your example.