Banks loaning to foreign governments?

I've recently been watching videos about private banks loaning foreign governments, particularly developing countries, money for projects such as infrastructure. I'm very interested in learning more about this with all this corona free time I have. I'm not saying I won't to work in this area, just learn more about it. Does anyone know how this works? Does anyone work in this area? And what type of banks do this work? I'm assuming commercial banks? Thanks for any answers.