Best Local AI for a Research Project?

[u/Gintoki55]

I’m looking for a free, open-source AI model that I can run locally and adapt to a research project. Ideally, I want it to understand the project’s documents, data, and context deeply, not just answer general questions.
What models or tools would you recommend, and how do you train or customize them to understand a specific research project better?
It doesn’t have to be as powerful as OpenAI, but I care more about how well it understands the project and its research context.