How can I load 2 random pages?

You can redirect users from home page to random page with this code (paste it to your functions.php)

function my_homepage_redirect() {
    if ( is_home() || is_front_page() ){
        $page = get_posts( [
            'post_type' => 'post',
            'posts_per_page' => 1,
            'category' => 1, // your category ID
            'orderby' => 'rand',
            'fields' => 'ids'
        ] );

        if ( empty( $page ) ){
            return;
        }

        wp_redirect( get_permalink( $page[0] ) );
        exit;
    }
}
add_action( 'template_redirect', 'my_homepage_redirect' );

If you want to pick random page OR random post, you can modify the ‘post_type’ parameter:
'post_type' => [ 'post', 'page' ],