Backend intern moving from MERN to Python + FastAPI — how should I ramp up quickly?

I recently started a backend internship at a startup where the backend stack is Python + FastAPI. During college I mostly worked with the MERN stack (Node.js, Express, MongoDB, React), so I’m comfortable with backend fundamentals like REST APIs, authentication, and database design, but this is my first time working with Python in a production backend.

Right now I’m trying to ramp up quickly on Python syntax, FastAPI concepts (routing, dependency injection, validation, async), and how real-world FastAPI projects are structured in production. For developers who have transitioned from Node/Express to FastAPI or who use FastAPI professionally, what learning resources helped you the most? I’m especially looking for good YouTube playlists, courses, or practical project-based tutorials that helped you get productive quickly.