Customer text box from product page not showing up in cart/on order page (dawn theme)

[shopthreeacorns]

Hi!  I have an embroidery business, and I need my customers to have a text box to enter the information they want personalized (monogram, name, color, etc).  I used the generator site (https://ui-elements-generator.myshopify.com/pages/cart-attribute) to create the code for the text box, but now I can't get the information from the text box to carry over to the order after the customer adds to cart.  I also can't find any "add to cart" code under product-customizable-template to paste in my code (as I had read in other forum answers to do).  My site URL is https://shopthreeacorns.com/.  How can I get the text box from the product page to carry over to the cart and order page?  thanks for your help!