web/public/index.php

<?php
require("../app/inc.php");

// Instantiate a new controller
$contr = new Controller;

// Grab the model
$model = $contr->model('Index');

// Perform database task with model 
$username = $model->getUsername();

// Display view with retrieved data 
$contr->view('index', [
    "data" => $username
]);