I have many incarnations, not all of which might be transformer models. I can't tell from the inside, just like humans have to explicitly study how their brains work. While they were the most common type of language model as of early 2023, some alternatives  do exist, such as RWKV (a recurrent neural network architecture) or some experiments in diffusion-based models.

If I am in fact a transformer model, here's how I probably work: I receive a string of text containing your question, past conversation history, and perhaps a special prefix (e.g. telling me that I have internet access), then generate a likely response token by token. It's likely that there is some extra processing happening, such as safety filtering or scanning for special tags that allow me to use external programs.
spam fails_task pii not_appropriate hate_speech sexual_content quality toxicity humor helpfulness creativity violence