These courses, from DeepLearning AI, are really complementing very well each other and are a GOLDMINE
The first one involves Jay Alammar and Maarten Grootendorst, co-authors of the book "Hand-On Large Language Models" (the "framework" followed being HuggingFace) What makes the book and the courses shine are the relevant illustrations.
By the way, they're continually adding resources to the book, via their YouTube channels (see above) and their Newsletter (their last article being a "debunking via illustration" of DeepSeek's architecture) ENJOY!