Is there a way to open the calendar of the datepicker

Hello @info98612

I suggest using the onChange() event handler on the first date picker to focus() on the second one.

const $chIn = $w('#checkInDP');
const $chOut = $w('#checkOutDP');

$chIn.onChange(() => {
    $chOut.focus();
})

Please note: Focusing on an element such as a dropdown menu or a date picker might not actually open it.

Hope this helps~!
Ahmad