ajax function on a page

[login to view URL] If you see this page it shows 3 products and then the red box and order form . the add to cart function is already working , what I want now is when people come first on the page they show till before the red box ( so only 3 products part is all what they see ) and when someone click go to checkout the full page opens up and the focus is to Enter your email address . If there is nothing added to cart and people try to go to check out it should show a warning saying Please add a product first . The page is made with div . Just to let you know it's not a wordpress page , just a single php page ## Deliverables [login to view URL] If you see this page it shows 3 products and then the red box and order form . the add to cart function is already working , what I want now is when people come first on the page they show till before the red box ( so only 3 products part is all what they see ) and when someone click go to checkout the full page opens up and the focus is to Enter your email address . If there is nothing added to cart and people try to go to check out it should show a warning saying Please add a product first . The page is made with div . Just to let you know it's not a wordpress page , just a single php page