Where to add code for custom fields in main profile tab?

I found the post on this forum for the code to add/edit to put custom fields in the main profile tab instead of in a sidebar or as separate tabs. I’m trying to create my own custom template using custom fields and I’d prefer to not have tabs at all but rather whatever custom template I come up with per my client’s requirements.

Anyway, I have the sample code (shown below) but I’m not sure where it goes. Does it go into the theme’s functions.php file? Or is it code to change in a specific template file that I place in my theme in a new geodirectory folder? Thanks in advance for any help you can offer to point me in the right direction.

This is the sample code from a previous post:
add_action(‘geodir_before_description_on_listing_detail’, ‘gd_profile_custom_content’);
function gd_profile_custom_content() {
global $post;
?>
<div class=”gd_profile_custom_content_wrapper”>
<div class=”column1″>
<div>
<?php echo geodir_get_post_meta( $post->ID, ‘custom_field_key_goes_here’, true ); ?>
</div>
<div>
<?php echo geodir_get_post_meta( $post->ID, ‘custom_field_key_goes_here’, true ); ?>
</div>
</div>
<div class=”column2″>
<<div>
<?php echo geodir_get_post_meta( $post->ID, ‘custom_field_key_goes_here’, true ); ?>
</div>
<div>
<?php echo geodir_get_post_meta( $post->ID, ‘custom_field_key_goes_here’, true ); ?>
</div>
<div>
<?php echo geodir_get_post_meta( $post->ID, ‘custom_field_key_goes_here’, true ); ?>
</div>
</div>
</div>
<?php
}