Can you guys me how to solve this step by step

Area of rectangle = Length x width, Area of triangle - (1/2) base x height
Surface Area is the sum of the area of all of the faces.

Your picture has 5 faces:
1) rectangle on the left
2) square in the middle
3) rectangle on the right
4 & 5) 2 congruent (identical) right triangles

Area of face #1: 5 x 4 = 20
Area of face #2: 4 x 4 = 16
Area of face #3: 3 x 4 = 12
Area of face #4: (1/2) x 3 x 4 = 6
Area of face #5: (1/2) x 3 x 4 = 6
Sum of the Area of the faces: 60

Surface Area of the figure is 60 units²

Volume = Length x width x height
             =     5      x    4    x     3
             = 60 units³

Volume of the figure is 60 units³