Additional option for User Role Editor

functions.php

<?php
add_filter( 'ure_role_additional_options', 'add_prohibit_access_to_admin_option', 10, 1 );

function add_prohibit_access_to_admin_option($items) {
    $item = URE_Role_Additional_Options::create_item( 'prohibit_admin_access', esc_html__('Prohibit access to admin', 'user-role-editor'), 'init', 'prohibit_access_to_admin' );
    $items[$item->id] = $item;
    
    return $items;
}

function prohibit_access_to_admin() {
    
    if ( is_admin() && !wp_doing_ajax() ) {
        wp_redirect( get_home_url() );
    }
}

More details here: https://www.role-editor.com/documentation/hooks/ure_role_additional_options/