You don’t have to register of GS1 India to get the UPC codes. Yes, you can buy it from eBay later.
Let me give you free 10 UPC codes from our side.
You need one UPC for one product and it really doesn’t matter how many products you are selling it. You don’t need to print UPC on each product, you need to put label on barcode label provided by Amazon on product carton in which you sending the stock to FBA. When you convert inventory to FBA and prepare to ship that time they provide you label.
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