Sorry if this is a naive question (I am in high school), but why do we always talk about ‘ideal’ stuff in physics? The conditions are not possible in real life so why bother with them, won’t the numerical values not accurately represent real life situations?
If you want to learn more on any subject, you need to start with the basics. Think of drawing, why do kids draw stick figures instead of photorealistic drawings of people? Gotta start somewhere and it’s easier, but still resembles reality enough for people to understand. If you want to make incredible art, you spend years honing your craft. If you want to do advanced math/physics, you spend years honing your craft.