If you do not own an air fryer, then you can either bake them in a conventional oven or deep fry them. To bake, place them in a baking tray in a single layer, brush with oil, and bake at 200 degrees C for about 20 minutes. Flip once midway and brush oil on the other side as well. To deep-fry, heat oil in a pan, and once it is hot enough, drop the spring rolls. Deep fry until golden brown and crisp.