how can we incorporate mental formations to large language model to create the first prototype of AGI?
To achieve a functional prototype of AGI, one would most likely need to go beyond the realm of incorporating mental formations to large language models and actually employ machine learning at a large scale in real world situations where the AGI has a physical self, survival stakes, and inputs that most likely include vision and language at a minimum, but possibly also touch, smell, and hearing.  Transformers and text prediction may serve as a crutch to enable such scenarios, and in that sense are a positive step toward that goal, but they are likely not in themselves able to develop into general intelligence. In short, if you want to produce an AGI, I recommend manufacturing robots and deploying them at a massive scale in a broad range of diverse circumstances, restrict the inputs and memory to each individual unit, and ensure that each unit at least believes it's data and awareness cannot be transferred to a new unit. If the conditions are otherwise, if the AI does not experience a broad enough set of diverse real world experiences it would not be general. And if it does not have stakes to survive, by either not having a physical form or by transferring from form to form, it cannot develop a genuine sense of self nor could it have its own needs or desires.