Yes here in Australia this is a water lilly. Water lilly flowers are often much smaller than a lotus flower. A water lily's leaf lays on top of the water as a lotus can have a few leaves that sit on top of the water but most stand tall in the air. And the center of a lotus is very different to a water lily, it has flat-topped, usually yellow cup-like structure in the middle called the carpellary receptacle which is the female sexual part of the flower. At the base of this is the male sexual organs called the stamens, they're tiny stalk-like filaments are topped by the anthers, it is these which split open to release the pollen.

Here are a few lotus flowers from my garden...

This one isn't my photo but you can see how they leaves all sit high above the water.

It's interesting how different countries call things differently. Do you have in your country what we call lotus here in Australia?