If the discounts are general and applicable to all, you may not need to use promo codes. However, if you have particularly won a coupon code or a discount code under certain conditions, you will have to use this code at the time of checkout to avail the offer.
Excitedly waiting for that
How to report a problem encountered while buying a product?
Why do I see different prices for the same product?
Are all products at Farosh genuine?
How can I list my products for sale at Farosh?
Does Farosh market the products that we list on the website?