> How if it hallucinate and gives you wrong code

Then the code won't compile, or more likely your editor/IDE will say that it's invalid code. If you're using something like Cursor in agent mode, if invalid code is generated then it gets detected and the LLM keeps re-running until something is valid.

> It is better to read documentations and tutorials first.

I "trust" LLM's more than tutorials, there's so much garbage out there. For documentation, if the LLM suggests something, you can see the docstrings in your IDE. A lot of the time that's enough. If not, I usually go read the implementation if I _actually_ care about how something works, because you can't always trust documentation either.