IVR asterisk script

I’m trying to get a link when a number in the IVR menu is presses

i know how to do it in the extentions.conf file but the problem is once i change a setting and apply it from FreePBX these settings are gone.

so i was wondering if there is a way to set up freepbx so that i can run a script

You should be putting your changes in extensions-custom.conf

then freepbx will include them and not overwrite them