Maybe this exercise will make you a better programmer.
As a habit, I don't stream code related to my workplace, it has too many risks. Even if you see parts and pieces and will not be able to make sense of it.
We don't have a single secret embedded in code and all of our secret files are encrypted using vault, even that is too risky for the clients we have.
I stream my personal projects and things like QnA etc...
Concerning 2: I would never code something actually sensitive on twitch. Fortunately I enjoy programming video games, so I can stream that with relative safety, but I wouldn't ever stream something from my real job for example.
This is my preferred method of programming as well -- start with a pile of working crap and refine. order out of chaos!
2: dual boot / set up an account on your system that doesn't contain sensitive stuff.
1. Show how horrible my code is.
2. Accidentally leaking sensitive stuff.