Depends on what I need to do. Learning enough to read some code takes less time than learning enough to fix bugs. Getting to sufficient competency to write code

Depends on what I need to do. Learning enough to read some code takes less time than learning enough to fix bugs. Getting to sufficient competency to write code from scratch takes longer, and leading a team and making architecture decisions will take longer still. I can usually read any C-family language without any study, because they are much more alike than different. I will need some reference material to fix bugs and make small changes. I may need a tutorial or a non-trivial code base to study to get to competency. Before I would lead a team or make expensive decisions I would want a couple of years experience with the language and ecosystem.