Durgapur has a range of shopping options centred around two main areas.
Benachity Bazaar is the old market — a 2–3 km strip of shops covering everything from food to electrical goods to textiles. The scale and variety are impressive for a city of this size. It has a real market atmosphere that the malls don't replicate.
City Center (the mall district) has Reliance Trends, Big Bazaar, Junction Mall, and Suhatta Mall. Standard Indian mall retail, but air-conditioned and convenient.
The city is not particularly known for crafts or souvenirs — there's nothing specific to buy in Durgapur that you can't get in Kolkata. But for day-to-day needs or window shopping, Benachity is more interesting than the malls.