Conditional: IF post creation date is in the first half OR last half of the year [closed]

Are you thinking of something like this?

if ( have_posts() ) {
    while ( have_posts() ) {
        the_post(); 
        if ( absint( get_the_date( 'n' ) ) <= 6 ) {
            // First half of year
            ...
        } else {
            // Second half of year
            ...
        }
    }
}