For example, in the product_details_full.tpl file, i want to add a variable whose value comes from item. How should you implement it?
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In addition, I found a pageHeader variable in the tpl file, but I didn’t see this variable in the Field Sets of the website. Why? Aren’t the variables in the Field Sets and the variables in the tpl file one-to-one corresponding?

I know i can expose information from the item records in NetSuite to my website by defining field sets.But I don’t know how to use the field set and in which tpl file it will be used