Hi Keyoma, I have never executed such a request myself, but I think you can achieve it by following this guide: https://docs.mendix.com/developerportal/deploy/access-restrictions/#41-example-scenario-1--restricting-access-based-on-an-ip-range 

You define a access policy by ip range and apply it to a path based restriction.

The path based restriction should block all anonymous calls except for the /p/public range for example.

Then you need to configure the path url for all public available pages in your Mendix app to start with /p/public

Hope this helps you on your way finding the solution.