Do I need to compulsorily retrain model on own dataset?

[onkar-99]

Hello I am new to this kinda projects and had a small doubt, possibly stupid. So the model you've trained will it be able to classify any person's lip movement irrespective of their accent , race etc? Or do I need to create a dataset of my own and then I need to train a new model? Because I've tried using available models but the predictions are wrong. Would be of great help if you could clearify this for me.