Woocommerce plugin customisation where do I put the code?

Hello – can anyone help a non coder?

Using a woocommerce plugin – would like to adapt my Shops front page.

Currently displays page description and images of subcategories.

Would like to be able to add content beneath these images – maybe some links or just to allow me to use Site Orgin Page Builder.

I know how to the Woocommerce product archive file into my theme and I might have found some code which might resolve my problem

function woa_content_after_shop() {
	echo "<p>Insert your Content here...</p>";
}

add_action( 'woocommerce_after_shop_loop', 'woa_content_after_shop')

Problem? I don’t know where to put it within the newly copied and renamed woocommerce.php file in my theme.

At the moment if I just paste in the code the text of the code appears at the bottom of the page.

I can follow instructions but as you can tell no coder.

Many thanks in anticipation