how to display both billing and shipping page on checkout?

-- HikaShop version -- : 3.5.1
-- Joomla version -- : 3.8.1
-- PHP version -- : 7
-- Error-message(debug-mod must be tuned on) -- : none

hi

this is from this thread as my question has evolved
www.hikashop.com/forum/checkout/895336-h...age-on-checkout.html

What i want to do instead is to display both billing and shipping page on checkout