Add a text box on a product page for my customers to be able to write something.

Site URL: https://www.noadecajou.com/shop/toy-bag

Hello,

When my customers go to my product pages, they have the possibility to personalise a product. They have to choose between yes and no. I would like them to be able to write the personalisation name on the product page itself (rather than completing a form that appears when they hit "add to cart"). I attached a screenshot. I would like to have a text box where the red rectangle is where they can write a name. I of course need to have this information as well when they make the purchase. 

Many thanks for your help.

Tina