But "devoting resources to deliberately moving closer to that 'success'" is just as much not-determined-by-you as everything else, whether it's fully deterministic in a classical physics sense, or partly deterministic, and part randomly quantum-influenced. The notion that you can influence yourself is true... your thoughts a second ago influence your thoughts now. So, through introspection, you can see that you're influencing yourself. But it's a mirage, because you're not at the root of the chain of causation going back to the first thought you had, so you don't control the thought you had a second ago, and you don't control any external factors (senses) that influenced you between your last thought and your current thought, so you don't control your thought now.
The reason you devote resources to moving closer to success isn't that you're "deciding" (from no prior state) to do that. Rather, your psychology is already such that you want to actively improve yourself, you don't have other psychological issues that would sabotage that desire, and you see a path to improve yourself. What better to do, then, than to move yourself along that path toward future success?