One of the best ways to learn JHipster and the technologies it supports is by contributing to JHipster directly. Refer to the contribution guide (https://github.com/jhipster/generator-jhipster/blob/master/CONTRIBUTING.md) for details about setting up JHipster for development.

You can contribute to the project in many ways, such as the following:

• If you find a bug, enter an issue in the GitHub project (https://github.com/jhipster/generator-jhipster), follow the guidelines in the issue template, run jhipster info, and provide the steps to reproduce it. You can also try to fix the issue yourself and submit a PR if you're successful.
• Work on open issues and feature requests. This way, you will learn the internals of JHipster and the technologies used along the way.
• Answer JHipster-related questions on Stack Overflow (https://stackoverflow.com/questions/tagged/jhipster).