Bioinformatics graduate who can understand Python code but can’t write it from scratch — how should I actually learn?

[u/Life-Detective-395]

I have a Master’s in Data Science with a previous background in wet-lab biology. My programming experience mainly came through my MSc, so I don’t have a traditional CS background.
At this point, I can usually **understand Python code when I see it**, explain what it is doing, and modify parts of it. But if you give me a problem and ask me to write the solution from scratch, I struggle — and I often rely on ChatGPT to get started.
I’m trying to figure out what the right way to overcome this is.
Should I:
go back and systematically learn Python/CS fundamentals through tutorials first, then start projects?
or keep building bioinformatics projects and use ChatGPT as a tutor/coding assistant while gradually becoming more independent?
I find learning programming purely through tutorials quite difficult and passive, especially because I’ve never studied CS formally.
**For people who came into bioinformatics from biology rather than CS: how did you actually learn to code independently? What should I be able to do before I consider myself “good enough” at Python for a junior bioinformatics role?**

[u/TheRNGuy]

Think of what task you need, then break it to smaller steps.