Maybe 10" & 8"...
Leaf effect??
Do you mean the sides of the cake?
Looks like they used a circle cutter to imprint overlapping circle shapes, then added dots where they touch.
The topper can be made by forming loops like you would to make a bow, one being longer than the rest, then covering where they meet with a little floral or medallion cut-out (on both sides).
Your fondant would have to be stiff in order for it to stand...so gumpaste or tylose is a must.