Hello! As I'm new on the forum, I might aswell start off with an introduction as that may be helpful given the purpose of the thread. I'm 19 years old and I'm currently in high school; my scientific knowledge is quite limited, I do have a basic knowledge of maths reaching up to and around calculus, I've taken courses in physics due to a genuine interest but I failed them because I've been such a lazy fool. I have a basic understanding of forces, but I lack knowledge in most other necessary fields within physics. Besdies that, I have a very limited understanding of basic chemistry and I'd say I'm quite well versed in biology and genetic engineering at basic levels. Now, to the true purpose of the thread. As the topic says, I want to understand the universe. My current goal is a complete understanding of both the special and general theories of relativity; and as I want to truly understand it, I assume knowing the maths behind it is essential. I'm also very interested in uncertainty and quantum mechanics, but I know close to nothing about those subjects. Nor do I know about string theory, but it does indeed look interesting as it, as far as I understand, could very well turn out to be a complete theory of everything. So I'm basically asking for help here; where do I start? Are there any good e-books or online courses that you can recommend? Am I in need of an education at a university, or could I find enough material on the internet or in the library? I won't be able to attend courses that costs money, but I'll check the library for books that could help me reach my goal. Thank you for reading, I hope that I'll be able to evolve intellectually during my time here on this forum.