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You have to write custom code to get the attachment id and post_parent by name/ slug or filename(if it has not been changed during the uploading of files).

Put the below code in your theme's functions.php file

if( ! ( function_exists( 'wp_get_attachment_by_post_name' ) ) ) {
    function wp_get_attachment_by_post_name( $post_name ) {
        $args = array(
            'post_per_page' => 1,
            'post_type'     => 'attachment',
            'name'          => trim ( $post_name ),
        );
        $get_posts = new Wp_Query( $args );
    
        if ( $get_posts->posts[0] )
            return $get_posts->posts[0];
        else
          return false;
    }
}

then you can call the function where you need it like below :--

$attachment = wp_get_attachment_by_post_name( $post_name );
// Replace post_name by the name/slug of the attachment
// It will give you an object, which you can render like below to get the ID and post_parent
if ( $attachment ) {
    echo $attachment->ID; // Gives the id of the attachment
    echo $attachment->post_parent; // Gives the post_parent id
    echo $attachment->post_title; // Gives the attachment title.
}