/**
 * Generate a list of information of all dates for a given month and year.
 * @param int $month month number of the year.
 * @param int $year 4 digit year number.
 * @return array
 *
 * @author oneTarek http://onetarek.com
 **/
function generate_date_list( $month, $year ) {

	$list = array();
	$month = intval( $month );
	if( $month < 0 || $month > 12 ) {
		return $list;
	}

	$year = intval( $year );
	if( strlen( $year ) != 4 ) {
		return $list;
	}

	//Find the number of days in a the given month.
	$date = date_create_from_format( "j-n-Y", "1-". $month . '-'. $year ); //"9-6-2013" 
	$num_days = intval( $date->format('t') );

	for( $d = 1; $d <= $num_days; $d++ ) {
	    
	    $date = date_create_from_format( "j-n-Y", $d. "-". $month . '-'. $year ); //"9-6-2013"          
	    $d_arr = array();
	    $d_arr[ 'd' ] = $date->format( 'd' ); //Day of the month, 2 digits with leading zeros	01 to 31      
	    $d_arr[ 'D' ] = $date->format( 'D' ); //A textual representation of a day, three letters	Mon through Sun 
	    $d_arr[ 'j' ] = $date->format( 'j' ); //Day of the month without leading zeros	1 to 31
	    $d_arr[ 'l' ] = $date->format( 'l' ); //A full textual representation of the day of the week	Sunday through Saturday
	    $d_arr[ 'F' ] = $date->format( 'F' ); //A full textual representation of a month, such as January or March	January through December
	    $d_arr[ 'm' ] = $date->format( 'm' ); //Numeric representation of a month, with leading zeros	01 through 12
	    $d_arr[ 'M' ] = $date->format( 'M' ); //A short textual representation of a month, three letters	Jan through Dec
	    $d_arr[ 'n' ] = $date->format( 'n' ); //Numeric representation of a month, without leading zeros	1 through 12
	    $d_arr[ 'Y' ] = $date->format( 'Y' ); //A full numeric representation of a year, at least 4 digits, with - for years BCE.	
	    $d_arr[ 'y' ] = $date->format( 'y' ); //A two digit representation of a year	Examples: 99 or 03
	    $d_arr[ 'full' ] = $date->format( 'l, F d, Y' ); //Friday, June 09, 2023
	    
	    $list[ $d ] = $d_arr;
	}

	return $list;
}

<?php
$list = generate_date_list( 6, 2023 );
echo "<pre>"; print_r( $list ); echo '</pre>';
?>

Array
(
    [1] => Array
        (
            [d] => 01
            [D] => Thu
            [j] => 1
            [l] => Thursday
            [F] => June
            [m] => 06
            [M] => Jun
            [n] => 6
            [Y] => 2023
            [y] => 23
            [full] => Thursday, June 01, 2023
        )

    .....
    .....
    .....

    [30] => Array
        (
            [d] => 30
            [D] => Fri
            [j] => 30
            [l] => Friday
            [F] => June
            [m] => 06
            [M] => Jun
            [n] => 6
            [Y] => 2023
            [y] => 23
            [full] => Friday, June 30, 2023
        )

)