JSFiddle - React, Tailwind, and code Playground

HTML

<select id="job"></select>
<input type-="text" id = "name">

JavaScript

var data = {
    "Company": [
        {
        "Position": "Manager",
        "Name": {
            "11": "joe",
            "12": "bill",
            "166": "John"
        }},
    {
        "Position": "Tech",
        "Name": {
            "11": "Bob",
            "12": "Cindy",
            "166": "Karl"
        }},
    {

        "Position": "Sales",
        "Name": {
            "11": "Sam",
            "12": "Ron",
            "166": "Sara"
        }}
    ]
};
$.each(data.Company, function(i, v) {
    // create option with value as index - makes it easier to access on change
    var options = $('<option/>', {value: v.Position, text: v.Position}).attr('data-id',i);    
    // append the options to job selectbox
    $('#job').append(options);
});

// bind change event
$('#job').change(function() {
    // cache this
    var $el = $(this);
    // get data-id attr from selected option
    var id = $('option:selected',this).data('id');
    // empty select
    $('#name').empty();
    // get name values for selected option
    $.each(data.Company[id].Name, function(i, v) {
        // create option elements
        var options = $('<option/>', {value: v, text: v});
        // append the options to name selectbox
        $('#name').append(options);
    });    
}).change();// trigger change() on page load to fill name selectbox