Below is a that reconstructs the core methodology such a book would cover: building a GPT-like LLM entirely from scratch using Python and PyTorch, focusing on foundational understanding rather than just using APIs.
Demystifying Large Language Models: Unraveling the Mysteries of Language Transformer Models, Build from Ground up, Pre-train, Fine-tune and Deployment
The title you provided corresponds most closely to popular project and subsequent book, " Build a Large Language Model (From Scratch)