$keyToSearch = 'age';
    $valueToSearch = 20;
    $multidimensional = [
        [
            'name' => 'Barry Allen',
            'age' => 20,
        ],
        [
            'name' => 'Steve Rogers',
            'age' => 99,
        ],
        [
            'name' => 'Peter Parker',
            'age' => 18,
        ],
    ];
    $indexInMultidimensionalArray = array_search($valueToSearch, array_column($multidimensional, $keyToSearch));

If $indexInMultidimensionalArray is equals to false the value searched was not found