Recorded at H2O World India, this talk from H2O principal data scientist and Kaggle Grandmaster Pascal introduces H2O's open source LLM Studio and the three-stage path to building a custom LLM: a pretrained foundation model, fine-tuning on curated data, and optional reinforcement learning from human feedback. He demonstrates fine-tuning in LLM Studio, then shows the resulting chat model answering questions, including a live example of the limits fine-tuning has without a connected knowledge database.