Question

although ice is solid still it flows on water? explain its structure​

Answer 1

Normally water contracts on cooling but from 4 degree Celsius it starts expanding.
due to this property ice is less denser than water and thus ice floats over water

Answer 2

Ice, despite being solid, has air trapped in it, decreasing it's density, making it lower than that of water, and as things less dense than water float on water, ice floats on water. Ice has a regular crystalline structure.