Add introduction page ou warning +18


I tried do add a introduction page, with index.html, mas interferes in the shop, products cant add do the cart, search dont work, etc…

How could I built a introduction page, to customers accept and enter the shop, or give up and go to other page, without interferer with the shop?

The other option is to create a warning +18 (like javascript), to customers accept to view the shop.

(sorry if my English isn`t the best…)

Best Regards,