从.json文件中调用php url

I have a json called response.json, its source code is shown below-

Requirement - when my app receives the word ["hi"] , a response is generated "hello". Instead of hard coding it, i want it to fetch the response from abc.com/reply.php. I dont know how to call php file from json file.

{
    "appconfig": {
        "headless": false,
        "darkmode": true,
        "isGroupReply":false
    },
    "bot": [{
            "contains": [],
            "exact": ["hi"],
            "response": "hello"
        },

Please help. Thanks in advance for your time.