Adopting while in Japan?

So I'm still young & don't plan on adopting for a few years. Me & my bf are starting to plan out our life. We are going to move to Japan where he will be an English teacher & I want to be a stay at home wife. We both want to adopt but I have some questions. We will be in a foreign country & I'm not sure how that effects being approved for adoption & if it's better to go through a certain country to adopt like this. We're not very picky what the nationality is but I do want an infant. His starting salary will probably be around 250k-300k a year. I would appreciate any facts on how the process works, what it takes to qualify, my chances of getting an infant, etc.