[Fixed]-Why am I unable to get response from my API in django rest framework via jquery?

You are passing your username and password incorrectly when making the request. This is discussed in this SO question.

Try this method instead.

$.ajax
({
  type: "GET",
  url: "http://127.0.0.1:8000/api/grocery/subcategories/?format=json",
  dataType: 'json',
  headers: {
    "Authorization": "Basic " + btoa("ratan:qazwsxedc123")
  },
  success: function (){
    console.log('ratan'); 
  }
});