Okay kiddo, imagine a flower that has both boy and girl parts - that's what we call a perfect flower! Just like how boys have their own special parts and girls have their own special parts, flowers also have their own special parts for reproduction.
The boy parts of the flower are called stamens and they have two parts - the anther and the filament. The anther is where the pollen is made, which is like the flower's sperm. The filament is like the support beam that holds up the anther.
The girl parts of the flower are called pistils and they also have two parts - the stigma and the style. The stigma is like a sticky pad that catches the pollen (the sperm) from the boy parts. The style is like a tube that leads to the ovary, where the eggs are kept.
Now, in a perfect flower, both the boy parts and the girl parts are in the same flower. This means that the pollen from the stamens can easily reach the stigma of the pistil, and then travel down the style to fertilize the eggs in the ovary. And just like that, the flower can make new seeds and grow into more flowers!
So, that's what we mean when we say a flower is perfect - it has all the necessary parts for reproduction in one neat little package. Cool, huh?