$dates = [];
$today = new DateTime();
for ($i = 0; $i < 30; $i++) {
$dates[] = $today->format('Y-m-d');
$today->modify('-1 day');
}
print_r($dates);
/*
run:
Array
(
[0] => 2025-04-10
[1] => 2025-04-09
[2] => 2025-04-08
[3] => 2025-04-07
[4] => 2025-04-06
[5] => 2025-04-05
[6] => 2025-04-04
[7] => 2025-04-03
[8] => 2025-04-02
[9] => 2025-04-01
[10] => 2025-03-31
[11] => 2025-03-30
[12] => 2025-03-29
[13] => 2025-03-28
[14] => 2025-03-27
[15] => 2025-03-26
[16] => 2025-03-25
[17] => 2025-03-24
[18] => 2025-03-23
[19] => 2025-03-22
[20] => 2025-03-21
[21] => 2025-03-20
[22] => 2025-03-19
[23] => 2025-03-18
[24] => 2025-03-17
[25] => 2025-03-16
[26] => 2025-03-15
[27] => 2025-03-14
[28] => 2025-03-13
[29] => 2025-03-12
)
*/