Dynamic Pricing using BigCommerce

Question

I'm working with BigCommerce and I have a product banner with dynamic pricing based on user input for width (w) and height (h). However, BigCommerce doesn't seem to provide any built-in functionality for dynamic pricing based on custom inputs.

Does anyone have suggestions on how I can implement this functionality using the BigCommerce API or perhaps through a plugin or custom development? Any insights or guidance would be greatly appreciated. Thank you!

Here is my code :

      const cartId = 'xxxxxx';
  const newCartAmount = 245.0;
  const apiUrl = `https://api.bigcommerce.com/stores/storeHash/v3/carts/${cartId}`;
  const accessToken = 'xxxxxxx';

  const headers = {
    'Authorization': `Bearer ${accessToken}`,
    'Content-Type': 'application/json'
  };

  const requestData = {
    cartAmount: newCartAmount
  };

  fetch(apiUrl, {
    method: 'PUT',
    headers: headers,
    body: JSON.stringify(requestData)
  })
  .then(response => {
    if (!response.ok) {
      throw new Error('Failed to update cart amount');
    }
    return response.json();
  })
  .then(data => {
    console.log('Cart amount updated successfully:', data);
  })
  .catch(error => {
    console.error('Error updating cart amount:', error);
  });