Link form to another form on a shopping cart

Also, please tell the development team that it would be wonderful if they could create a way to relationally link certain forms together for the purpose of submitting form information from different forms into a shopping cart. As you can see from the choir music product that I have for sale on this form, this song has many different related components that need to be all listed on the same page (which I am not able to accomplish in my Shopify e-commerce store). However, with JotForms current setup, the customer needs to checkout at the bottom of my form
instead of going to another possible song (separate form page) to add other possible songs to the cart before checking out.

Hi, 

Unfortunately, It is not possible to add other possible songs to the shopping cart before checking out for now. this feature have already submitted as a request feature ticket. If you want to create full-fledged e-Store, you can check the Prestashop or Shopify websites.

In addition to that, you can use the PayPal option. This option will allow you to configure multiple products and setup the payment through PayPal. At that time, user can "add to cart" after customer fill the form they have to make a payment.

https://www.paypal.com/webapps/mpp/shopping-cart

If you have any question or issues, please do not hesitate contacting us. We will be glad to assist you.