Tax Caulte Problem

Hello,

1. The tax calculation always wrong.
2. Could you please give me informations as more as possible for how to add different products on different pages?
3. All products(except sale products) are marked “New” on the top right of image, I don’t need it, how to remove it?
4. How to change font colour and size for “carte page, checkout page, signle product page”?

Thanks.
Regards