--help - Print yo help menu with the list of found generators.
--[no-]insight - Toggle anonymous Insight tracking which helps us improve Yeoman. Using either of these flags on the first run will prevent you from being prompted about it interactively. The flags can also be used to change it later on.
--generators - Print available generators.
Running yo doctor command can help you troubleshoot common issues.
If doctor doesn't help, then check opened issues for a similar problem. Open a new issue if your problem haven't been reported yet. Make sure to always include the version of yo (yo --version) and Node.js (node --version) you use.
If your issue only occurs using a generator, please report the issues on the generator's repository.