If you have done enough beginner's exercises in SQL (like the ones on W3Schools) and want to learn queries that are common in actual jobs or programming assessments, I encourage you to do the exercises on SQL Bolt. This free website is meant for beginners, but it progresses into queries that have a decent level of sophistication.
If you can complete all of the exercises successfully, then you will have grasped most of the SQL concepts that employers seek in junior or intermediate jobs in statistics, data analysis, or data science. I encourage you to do all of the exercises multiple times over several days, just to make sure that you really absorb all of the underlying concepts.
Happy practicing!