[Theme: Hatch] Portfolio page displaying several categories

Hello there! First of all, I’ve got to say that my WordPress skills are not really good but I’m trying to learn ??

Well, the thing is that I’m trying to run this website: https://www.saravilassantiago.com based on Hatch theme, which, if needed is built with Hybrid framework.

It works like charm except for the “Portfolio” part. Here’s is the thing: I’m graphic designer, so I have works in really different areas (each one will be set in a different category) but I can not display multiple categories in one page. In fact, I can not even display one properly.

There’s not a “category.php” file or similar for the Category template. It’s something about hierarchy because I found this in a file named “template-hierarchy.php”:

function hybrid_taxonomy_template( $template ) {
	/* Get the queried term object. */
	$term = get_queried_object();
	/* Remove 'post-format' from the slug. */
	$slug = ( ( 'post_format' == $term->taxonomy ) ? str_replace( 'post-format-', '', $term->slug ) : $term->slug );
	/* Return the available templates. */
	return locate_template( array( "taxonomy-{$term->taxonomy}-{$slug}.php", "taxonomy-{$term->taxonomy}.php", 'taxonomy.php', 'archive.php' ) );
}

But I can’t find anywhere the taxonomy.php file neither.

So, I was trying to copy and paste the code from the original home.php, where you got posts displayed (you can see the Hatch original demo here: https://devpress.com/demo/hatch/). Then, I added to the top the query_posts line to display just the category I want, so I had this:

<?php do_atomic( 'before_content' ); // hatch_before_content ?>
       <?php query_posts('cat=3'); ?>
	<div id="content">
		<?php do_atomic( 'open_content' ); // hatch_open_content ?>
		<div class="hfeed">
			<?php if ( have_posts() ) : ?>

Plus header, the rest of the copied code from home.php and footer.

For some reason, this shows up like this: https://saravilassantiago.com/portfolio/ instead of showing up like this: https://saravilassantiago.com/category/web/

I tried changing the line of query_posts, but it doesn’t want to work!

Any suggestion about this issue?

Also, any suggestions (when this part is solved) about how to add multiple categories? (Should be something simple like <h1>BRANDIND</h1> *here branding category posts* and so on with the rest of categories I need to add)

Thank you so much in advance! I’ve been reading and messing the code around for days! :/