Hi ThasnimolVSam22d007
You can add your own classes to an already existing/trained model, by retraining it from a checkpoint along with your new training data. I suggest you look up a few tutorials. I've seen shoes, person, face (haven't yet seen one for goggles), but all as separate models. Your best bet is looking for something like yolo, which usually already has ~ 80 classes.
Hope this helps,
Jaka