Reply To: Changes to single product page

Hello,

I saw the screenshot you attached.

1) The add to cart button is on the next line due to the Custom CSS you added. Please remove the Custom CSS you added and try adding the following Custom CSS in the Global Custom CSS area to make the add to cart full width.

.product-type-simple form.cart > button, .woocommerce-variation-add-to-cart > button {
    flex-grow: 1;
}

.product-type-simple form.cart, .woocommerce-variation-add-to-cart {
    display: flex;
}

2) You can add a custom tab for the product from the Edit product.

Screenshot for Clarification: https://ibb.co/kSs9kqS

Regards.
Xtemos Studios