Une fillette belle comme une fleur. -- A girl, beautiful as a flower.

Think of "belle comme une fleur" as one big compound adjective which follows the noun fillette.

Hi D,

It is the case that most adjectives appear after the noun.

However there are some that go before the noun and they are remembered by using "BAGS"

B  --  beauty, A -- age, G -- good or bad, S -- size

Adjectives which are used to describe the characteristics above tend to appear before the noun.

Hope this helps.

Bonne continuation.

Jim