How can I get a internship dealing with law as a high schooler?

You are correct that most direct actors in the legal system - lawyers, courts, government agencies - tend to hire mostly law students and (much less frequently) college students. The reason is that that most firms, courts, etc. already have a paid administrative staff to do the admin-type work that a high school student would be capable of doing (filing, answering phones, responding to emails, etc). The only part-time need that these types of employers tend to have are for actual help with legal research, legal writing, drafting, etc. which requires legal training, so high school students just aren't qualified to do those types of jobs (yet). The exception is if you happen to know, or have any connection to any lawyer or judge. I have seen high school kids get paid and unpaid jobs with judges, law firms, etc through connections. Is anyone in your family a lawyer, or does anyone in your family know a lawyer? Ask them to reach out to that lawyer and see if they would either have any paid work that you could do, or maybe even if they would be willing to let you come in and shadow them for a few days or weeks? I would also ask your high school counselor to see if they know of any programs that would allow a high school student to shadow a lawyer or a judge - there may be something like that in your area!

You also mentioned politics, and while I consider that to be a different field than the legal field, if that interests you, then you should be able to volunteer or intern for a political campaign. Politicians and campaigns regularly hire high school students as interns, and also have lots of high school students as volunteers. Your name indicates that you may be a high school junior? The next big political campaign season at the federal level will be for the 2022 midterms - so it's possible that you could get in involved in the mid-term elections in your senior year. Look for you US congressional and Senate races to see who is running (there will likely be both a primary and general election, with the primary being much earlier). There will also be dozens, maybe 100s of local elections for state reps, state senators, mayor, town or village council, sheriff, and a plethora of judges. Check out all of the local races in your area, find a candidate that you like and reach out to see if you can volunteer. Or check out their social media pages to find out if they are hiring interns (most are!). There could also be local elections next year in your area, or even be special elections (if you live in Georgia right now, you might have heard that there are two Senate run-offs happening in January). I would say that you should definitely be able to find a politician or a campaign to work for before you graduate from high school, and you'll have even more opportunities when/if you go to college. And, once you are in college, be sure to check in with the career services office at your school early on and ask about opportunities to work or do an internship for a legal employer. There should be a lot more opportunities for you at that point.

Good luck!

It really depends on what's near you, and your best bet is typically to do local research and ask places you might want to work at.

In politics, races up to congressional races will often hire high schoolers or allow you to volunteer. However, since the 2020 election cycle is passed, and the next major one is the 2022 midterms, you might not be able to do this at a high level.

For law and the court system, there's a lot of local variations. My best advice is to research your local area's courts, law firms, and DA/Public Defender offices. If you can't find anything, try calling them.

Sorry that this isn't more helpful, but it's a big matter of local variations.

Best of luck with your college applications!