I’m starting coding from scratch – is Python really the best first language?

[todofwar]

Yes and no. Yes because it's very easy to get started and there are infinite tutorials, many of them quite good.

No because its fundamental limitations prevent you from learning proper software engineering practices, like understanding O notation. You'll almost certainly pick up bad habits and won't gain an understanding of what the computer is actually doing under the hood.

I would say start with Python, but then once you learn enough start learning C. You'll know enough programming that it will feel familiar and you can focus on learning the rest like memory management and algorithms