How did you find your scientific niche?

Hello scientists and science enthusiasts! I want to ask for some advice. I am a budding scientist interested in physical oceanography with a keen study interest in coral reefs. I am particularly interested in research focusing on the impacts of coastal urbanization, sea level rise, nutrient enrichment, and climate extremes, as these issues align directly with my interest in coastal processes, climate adaptation and sustainable resource management.

I know that all together, these are all very broad components which leads me to my question: in such a big world of science how did you find your niche?

All thoughts and insight appreciated!