Сергей Мирченко

<?php 

$catalog = [
    [
        'id' => 1,
        'p_id' => '',
        'name' => 'Parrent Name'
    ],
    [
        'id' => 2,
        'p_id' => '',
        'name' => 'Parrent Name'
    ],
    [
        'id' => 3,
        'p_id' => '',
        'name' => 'Parrent Name'
    ],
    [
        'id' => 4,
        'p_id' => '1',
        'name' => 'Parrent Name'
    ],
    [
        'id' => 5,
        'p_id' => '2',
        'name' => 'Parrent Name'
    ],
    [
        'id' => 6,
        'p_id' => '3',
        'name' => 'Parrent Name'
    ],
    [
        'id' => 7,
        'p_id' => '4',
        'name' => 'Parrent Name'
    ],
    [
        'id' => 8,
        'p_id' => '5',
        'name' => 'Parrent Name'
    ],
    [
        'id' => 9,
        'p_id' => '5',
        'name' => 'Parrent Name'
    ],
    [
        'id' => 10,
        'p_id' => '9',
        'name' => 'Parrent Name'
    ],
];

function recursive($data, $p_id = 0, $level = 0)
{
    
    echo "<ul>";
    foreach ($data as $category) {
        echo "<li>";
        if ($category['p_id'] == $p_id) {

            $str = '';
            if ($level > 0) {
                for ($i=0; $i < $level; $i++) { 
                    $str .= '-';
                }
            }

            if ($category['p_id'] == $p_id) {
                echo $category['name'] . "<br>\n";
            }

            $id = $category['id'];
            $level = $level + 1;

            recursive($data, $id, $level);

        }
        echo "</li>";

    }
    echo "</ul>";
}