INDEX.PHP
<?php get_header(); ?>

<div class="container">
	<div class="row">
		<div class="col-sm-12">
			<h1 class="title-areas">Destaques</h1>
			<div class="post-area">
				<?php get_template_part('template_parts/post'); ?>
			</div>
		</div>
	</div>
	<div class="row">
		<div class="col-sm-7">
			<h1 class="title-areas">Todos os posts</h1>
			<?php get_template_part('template_parts/posts'); ?>
		</div>
		<div class="col-sm-5">Aqui vem a sidebar</div>
	</div>
</div>
<footer>
	<?php get_footer(); ?>
</footer>

AREA DOS 3 POSTS
	<?php query_posts('showposts=3'); ?>
<?php	if(have_posts()): ?>
	<?php while(have_posts()): ?>
		<?php the_post(); ?>
		<h1><?php the_title(); ?></h1>
	<?php endwhile; ?>
<?php else: ?>
	<h3>Não há posts para listar</h3>
<?php endif; ?>

AREA DOS 6 POSTS
<?php query_posts('showposts=6'); ?>
<?php	if(have_posts()): ?>
	<?php while(have_posts()): ?>
		<?php the_post(); ?>
		<h1><?php the_title(); ?></h1>
	<?php endwhile; ?>
<?php else: ?>
	<h3>Não há posts para listar</h3>
<?php endif; ?>