Project in resume

Good afternoon In vacancies and during interviews, employers always refer to the need for practical experience using Java. Where to start - publishing complex tasks with JavaRush on GitHub? Or does the employer mean his own Java project? There is also a lack of understanding - what can be done in Java and what cannot be done? With virtuosity, of course, there are no boundaries, but where should a beginner start so as not to get bogged down in development for a year on the first project? Thanks in advance for your advice and help!