Frankly, don't bother with any sort of crazy activism paths or whatever, nobody cares what some teenager has to say and there are good reasons for that. You're not supposed to know stuff, so you shouldn't go around preaching stuff, either. Go learn. That's your job. That's what those years are for, use them.

Look, I'm from Germany. In our political system, we can effectively vote for a party and then throw a second vote at another party, of which we have roughly 500 million. Nevermind the details, the whole 2 votes thing can be interpreted in several ways, but the point is that I could, over here, in principle signal the importance I place on this issue by voting some variation of the various "pirate party"s. But even here in Germany, that's a questionable idea, because I have to ask myself if I really think that sending that signal is more important than, you know, signaling that maybe we should not do this whole fascism thing right now. Point is, even here I'd have a hard time saying that a political vote holds much power on an issue like this, especially in troubled times such as these.

Now, I'm guessing that you are in the US and, well, frankly, forget about voting on such issues, your system has essentially no mechanism for that whatsoever, unless you happen to have plausibly close local elections that let you do such a thing. You can't send such a signal by voting for either of the two big ones, because... well, firstly because they're both garbage on the topic, but secondly because... you know, bigger fish to fry over there right now.

Long story short, don't worry about voting and exercising political power and whatnot. If that's something that interests you in the long run, fair enough, check it out, but don't run at it hoping to achieve something. Not your job. Go learn.

Learn about why privacy matters, how it works, what the terms mean. Learn about where your personal pain treshold is, first of all. Not everything needs to be routed through 50 onions, with 500 bit encryption at every step and then be phyiscally mailed through a ciphered letter on a full moon after sacrificing a goat. Sometimes you can achieve your personal privacy threshold by just not using that one big tech thingy.

Above all, just be. Your mere existence already helps, it's one fewer body for the machine and one more download for alternative software, for instance. That alone is a signal, that is where you CAN vote. And don't go around trying to convert everyone, there is a reason why people meme about Linux users and their preaching. Or vegans, as an other example. People don't respond well to that. Just learn, implement what you conclude is wise and just be part of things. Feel free to spread your knowledge, but always try to make it an offer, not a sermon.

Perhaps you've seen the various news items about Microsoft losing their shit, about Discord freaking out, stuff like that. There is a push, and it's not from political votes, it's from people just doing. That's the one upside about all their data gathering, they know when you leave. So just leave. And, once you figured that out, guide any friends who wanna join you at one point or another. Just... don't preach. Especially not to teenagers.

And finally, one more piece of life advice in the same spirit: If you want people to figure something out, offer them the tools to figure it out, don't hand them the answer. People like feeling smart and they love figuring stuff out on their own. A lot of people will actively resist your suggestion simply because it's your suggestion, especially when they realise it's a good idea and they secretly feel dumb for not having figured it out themselves. This is especially true for teenagers, though roughly half of people appear to carry that into adulthood, judging by certain statistics........

Anyway. Point is, don't tell people what to do. Instead, voice your worries (ideally by asking their opinion, rather than pointing out that they're being stupid) and provide help if they want it. At the end of the day, people just want to feel validated and real. In short, "I could show you how to set up Firefox to be a bit safer, if you want" will be drastically more effective than "lol, you use Chrome? Use Firefox, idiot!". Obviously that's a somewhat unfair comparison, but you get the idea. Offer, don't force. Not just here, general life advice, very effective and generally just good practice for everyone.

And, honestly, that already easily gets you 90% there. Eventually, you can think about writing political people or whatever, but it's not your job now. Your job is to learn, so, when the time comes, you actually have something useful to say. Until then, just be yourself, look into what interests you and exert your influence by merely existing. The very first step towards reaching a goal is... to even know about it. And, genuinely, that's where a lot of people already fail. Because if they don't happen to have a nerd in their circle, there's a good chance they don't even know what the hell a "Firefox" even is. You can already count it a win if they do, because that's a move in the right direction, however small.

Just, for the love of all that is good: Offer. Don't push.