1. To me, abstractly, a software engineer is someone who can going into a new language/situation and the result would be the best possible outcome given the supplied circumstances.
2. I think it would be fair to call yourself a software engineer once you have verified your ability to master multiple languages, and finished multiple projects, as the concepts behind them are the same.
There is no rule that dictates when someone becomes a software engineer. It happens when you're confident enough that you know your stuff, which is subjective. To me, it's when you can learn any language/project, given a reasonable (subjective to other SEs) amount of time.
2. I think it would be fair to call yourself a software engineer once you have verified your ability to master multiple languages, and finished multiple projects, as the concepts behind them are the same.
There is no rule that dictates when someone becomes a software engineer. It happens when you're confident enough that you know your stuff, which is subjective. To me, it's when you can learn any language/project, given a reasonable (subjective to other SEs) amount of time.