Ada particularly the SPARK subset. It’s approach is quite different than most languages, focusing on minimising errors and correctness. It’s fairly difficult but I like to use it to teach people to actually understand the problem and how to solve it before they ever write the code.
Nope. I only learned to use computers as an adult, and only learned programming incidentally as a tool for other work.
The truth is that it’s actually much faster to learn as an adult, you just have more momentum if you start as a child.