Post input field text from product page to cart

I’m trying to get form input from the product page to the cart, but no luck so far. This is what I did:

Made a file called custom-input.php with an input field inside.

<input type="text" id="custom-input" name="custom-input" value="custom-input">

Added the field inside the add to cart form (simple.php) on the product page using an action hook. I only want it to display if the product has a certain tag so there’s an if statement too.
```
<?php if ( has_term( 'custom-input-tag', 'product_tag' ) ) {
do_action( 'woocommerce_add_custom_input' ); 
} ?>
```

Added a row inside the table in cart-totals.php to display the form output.

<tr class="custom-input">
    <th><?php _e( 'Your custom input is', 'woocommerce' ); ?></th>
    <td><!--Custom input field text comes here--></td>
</tr>

After doing some research inside Woocommerce files I found that they use the WC cart class. It stores user data within sessions. The cart totals for example are retrieved with this code:

   function wc_cart_totals_subtotal_html() {
   echo WC()->cart->get_cart_subtotal();
   }
   <td><?php wc_cart_totals_subtotal_html(); ?></td>

I think this is the way to go, but failed to make a function that puts the form input on my cart page. If anyone has thoughts on this, help would be much appreciated!