If your school doesn’t offer any clubs, that’s probably something you should bring up in your application. You could say that your incentive to apply to private schools is because they offer much more opportunities that could help you expand further on your passions.
You probably meant that you “can’t find any opportunities nearby”. I suggest you to do a google search on competitions/research projects that focus on what you’re passionate about (like biology). Since right now we’re in a COVID lockdown, many organizations are hosting their competitions online, so anyone from anywhere could join.