Learn to use Queryverse
All packages in the Queryverse are completely documented. That documentation is accessible via the github homepage for each individual package. For some packages the documentation is simply the README file, other (more complicated) packages have more extensive documentation.
Julia for Data Science is the beginning of a book that covers Queryverse. At this point the emphasis is on "beginning": so far only a few chapters have been written, so this is not a comprehensive introduction yet. But the material that is available at this point should be useful.