Lock BuddyPress to only logged in users

bp-custom.php

<?php
 
// **** Privacy ********
function restrict_access(){
global $bp, $bp_unfiltered_uri;
 
        // If user is not logged in and
        if (!is_user_logged_in() &&
                                (
                                        // The current page is not register or activation
                                        !bp_is_register_page() &&
                                        !bp_is_activation_page()
                                )
               
                )       {
                                // Redirect to registration page. Change /join to your register page slug
                                bp_core_redirect( get_option('home') . '/join' );
                        }
}
 
add_action( 'wp', 'restrict_access', 3 );