Zoho CRM.

I have a drop down named ''number of items'' which ranges from 1-100. Below that I have a subform with 18 fields. 

Here is an example of what I need for this section: 

Number of items: 10 

Subform (all 18 fields) show up 10 times

I have attached an image of workflow for easier understanding. How do I create this? Is there a code I need to use? 

I was wondering if there is a way of doing this through workflow?