Possibly relevant: the academic papers of Bard Harstad on game theory of international treaties (esp. in climate change policy).
https://www.sv.uio.no/econ/personer/vit/bardh/dokumenter/participation.pdf
https://www.sv.uio.no/econ/personer/vit/bardh/dokumenter/cmp.pdf
https://www.sv.uio.no/econ/personer/vit/bardh/dokumenter/iea.pdf
https://www.sv.uio.no/econ/personer/vit/bardh/dokumenter/prb.pdf
I don’t know international issues or bio well, but fwiw I would resist the urge to spend a ton of time thinking about planning various possible career paths in the distant future as an young undergrad. The future is hard to predict. I’d focus on getting the skills that will give you options.
Respectfully, you may need to just “put your head down” for a couple years and just focus on studying really hard and not think too much about the distant future. I’d start by focusing your studies on foundational subjects like math and then gradually shift your coursework/time more to applied subjects (e.g. statistics → bio) as you go through undergrad and beyond. Take hard stem classes (within your level) and try to learn as much math as possible. Don’t worry about getting straight A’s. B’s in hard classes is better than A’s in easy classes. If you can understand, say, scientific computing, MV calc, linear algebra, real analysis + functional analysis (optional), probability, bayesian statistics, and machine learning/deep learning, and you also you also background in bio (esp. if you have some research experience), you will likely be accepted to good phd programs (let alone masters) in U.S. and elsewhere. Private sector jobs or research assistantships will likely also be available.
Every once in a while come up for air and reorient your direction. But I think it’s the long slow slog (through the textbooks, psets, coding assignments) that will bring you success rather than getting the perfect career plan from day one.