I have almost zero knowledge with Wordpress and Wocoommerce cores and api's so, please bear with me.

I have showing ~140 products on custom page (e.g. not the default shop page for woocommerce) trough WooCommerce Product Filter.

The products are on page and everything is fine except there is no way to show dropdown Products per page which I can choose how many products to show on page.

So, I've found some tutorials and currently I have this in my function.php

add_action( 'woocommerce_before_shop_loop', 'ps_selectbox', 25 );
function ps_selectbox() {
    $per_page = filter_input(INPUT_GET, 'perpagee', FILTER_SANITIZE_NUMBER_INT);     
    echo '<span>Per Page: </span>';
    echo '<select onchange="if (this.value) window.location.href=this.value">';   
    $orderby_options = array( '8' => '8', '16' => '16','32' => '32','64' => '64' );
    foreach( $orderby_options as $value => $label ) {
        echo "<option ".selected( $per_page, $value )." value='?perpagee=$value'>$label</option>";
    }
    echo '</select>';
}
add_action( 'pre_get_posts', 'ps_pre_get_products_query' );
function ps_pre_get_products_query( $query ) {
    $per_page = filter_input(INPUT_GET, 'perpage', FILTER_SANITIZE_NUMBER_INT);
    if( $query->is_main_query() && !is_admin() && is_page() ) {
        $query->set( 'posts_per_page', $per_page );
    }
}

function render_ps_sel() {
    return ps_selectbox();
}
add_shortcode( 'ps_selectbox', 'render_ps_sel' );

I'm render the dropdown menu trough the shortcode above [ps_selectbox] but whatever I choose the number of the products on the page is always same and nothing change.

I have almost zero knowledge with Wordpress and Wocoommerce cores and api's so, please bear with me.

I have showing ~140 products on custom page (e.g. not the default shop page for woocommerce) trough WooCommerce Product Filter.

The products are on page and everything is fine except there is no way to show dropdown Products per page which I can choose how many products to show on page.

So, I've found some tutorials and currently I have this in my function.php

add_action( 'woocommerce_before_shop_loop', 'ps_selectbox', 25 );
function ps_selectbox() {
    $per_page = filter_input(INPUT_GET, 'perpage', FILTER_SANITIZE_NUMBER_INT);     
    echo '<span>Per Page: </span>';
    echo '<select onchange="if (this.value) window.location.href=this.value">';   
    $orderby_options = array( '8' => '8', '16' => '16','32' => '32','64' => '64' );
    foreach( $orderby_options as $value => $label ) {
        echo "<option ".selected( $per_page, $value )." value='?perpage=$value'>$label</option>";
    }
    echo '</select>';
}
add_action( 'pre_get_posts', 'ps_pre_get_products_query' );
function ps_pre_get_products_query( $query ) {
    $per_page = filter_input(INPUT_GET, 'perpage', FILTER_SANITIZE_NUMBER_INT);
    if( $query->is_main_query() && !is_admin() && is_page() ) {
        $query->set( 'posts_per_page', $per_page );
    }
}

function render_ps_sel() {
    return ps_selectbox();
}
add_shortcode( 'ps_selectbox', 'render_ps_sel' );

I'm render the dropdown menu trough the shortcode above [ps_selectbox] but whatever I choose the number of the products on the page is always same and nothing change.