To the best of my knowledge, this would be the first time I’ve recommended CF to you. Let alone one of the first times I’ve made the recommendation on this forum.
Regardless, if you think you’re more capable developer than a multi-billion dollar company with countless data centers globally, be my guest.
At the core, you need to determine if a user is from a certain country. You can use a IP address decoder, although I suspect you think you’re smart enough to write one yourself, I would recommend a API like ipinfo.com. Once you determine the users country, simply block them if they’re from a blacklisted country.
Conceptually, this is a very simple task to accomplish. It worries me that you aren’t able to begin developing this on your own without asking for a starting point. A capable developer doesn’t need to ask such simple questions.
Best of luck to you. 😆