If it’s worth saying, but not worth its own post, here's a place to put it.
If you are new to LessWrong, here's the place to introduce yourself. Personal stories, anecdotes, or just general comments on how you found us and what you hope to get from the site and community are invited. This is also the place to discuss feature requests and other ideas you have for the site, if you don't want to write a full top-level post.
If you want to explore the community more, I recommend reading the Library, checking recent Curated posts, seeing if there are any meetups in your area, and checking out the Getting Started section of the LessWrong FAQ. If you want to orient to the content on the site, you can also check out the new Concepts section.
The Open Thread tag is here. The Open Thread sequence is here.
Welcome from a fellow German here! IIRC I also stumbled on Less Wrong via HPMoR, though back then the story wasn't even finished yet.
I must say, I'm impressed with the quality of your English writing at that age!
If you're ambitious and driven to choose a career to make the world a better place, check out the resources at 80,000 Hours from the Less-Wrong-adjacent Effective Altruism community. They've done lots of research and thinking into various career paths and their expected impacts, requirements, etc. They're not perfect, in that they e.g. expect a lot from their readers, and below a certain level of ambition and conscientiousness much of their advice might not be particularly applicable. But now might be a good time to check whether their resources could be useful to you.
If you think you could benefit from chatting with someone to get a rough overview of the landscapes of Less Wrong or effective altruism, I'm available to chat. I'm mostly a longtime lurker in the community, but I do have enough familiarity with it that I can at least point towards further resources on most topics.