Force user to agree to terms and conditions?

-- HikaShop version -- : latest
-- Joomla version -- : 3.3.0
-- PHP version -- : 5.5.11
-- Browser(s) name and version -- : IE 11

I see there's a place for entering a terms and conditions article, and I did that, but it doesn't force the user to choose to accept them at checkout. How do I do this?

Make "Terms and Conditions" part of your checkout workflow. If it's not in there, it won't be displayed.