Lateral surface area just means the surface area, but excluding the top and base, so for a pyramid the lateral surface area would just be the surface area of all four triangles.
To find the surface area of the four triangles, you first do base × height = 32 × 24 = 768, and then divide that by 2 which is 384. Now you can just multiply this by 4 and get your answer as 1,536 square centimeters.
I hope this helps!