You can try something like this:
1- Create a new empty page, white 50x50. Set this page as the index. Rename the old index to something where the “allowed users” would be redirected, like “landing” or something else.
2- Create a new page where the “not allowed users” would be redirected like “soon”, and display here the content your “non-allowed” users will see, like coming soon… etc.
3- We need to get the user’s I.P. to know his location. You can use Ipify: https://api.ipify.org/?format=json (there are plugins in the marketplace) or add a new connection (GET) in the API connector with the above URL.
4- Now, we need to know based on the I.P. what country it is. I suggest using Ipapi (30,000 runs/month free). Add a new connection (GET) using this URL: https://ipapi.co/X.X.X.X/json/ replace the X.X.X.X. by the I.P. from step 3 (using dynamic tags). Example: https://ipapi.co/126.96.36.199/json/
5- Based on the “country” or “country_name” response from step 4, you can decide to redirect to “landing” or “soon”.
PS: Steps 1 and 2 are optional. You also can run 3-4-5 in your current index page and if you detect any non-allowed country, redirect to x page / show pop-up / whatever.
Let me know if you have any questions,