I'm going out with my small business to another country. What do I need to know?

Hello! I'm working on a new freelance website - https://cashbox.money/. Now our service is launching for English and French speaking audiences, but soon we plan to launch it in other countries as well. And there's the problem - we don't actually understand what SEO strategy should we use. We don't have enough experience and knowledge to launch project in new countries. What can you advise? I'll appreciate anything you can say!